diff --git a/.gitignore b/.gitignore
index b357a0c..5c58dbb 100644
--- a/.gitignore
+++ b/.gitignore
@@ -368,4 +368,4 @@ FodyWeavers.xsd
 */**/obj/Release   
 */Migrations
 /exercise.wwwapi/appsettings.json
-/exercise.wwwapi/appsettings.Development.json
+/exercise.wwwapi/appsettings.Development.json
\ No newline at end of file
diff --git a/exercise.webapi/DTO/AuthorDTO.cs b/exercise.webapi/DTO/AuthorDTO.cs
new file mode 100644
index 0000000..7623cab
--- /dev/null
+++ b/exercise.webapi/DTO/AuthorDTO.cs
@@ -0,0 +1,13 @@
+using exercise.webapi.Models;
+
+namespace exercise.webapi.DTO
+{
+    public class AuthorDTO
+    {
+        public int Id { get; set; }
+        public string FirstName { get; set; }
+        public string LastName { get; set; }
+        public string Email { get; set; }
+        public List<BookPublisherDTO> Books { get; set; }
+    }
+}
diff --git a/exercise.webapi/DTO/BookDTO.cs b/exercise.webapi/DTO/BookDTO.cs
new file mode 100644
index 0000000..e8c19c7
--- /dev/null
+++ b/exercise.webapi/DTO/BookDTO.cs
@@ -0,0 +1,26 @@
+using exercise.webapi.Models;
+
+namespace exercise.webapi.DTO
+{
+    public class BookDTO
+    {
+        public int Id { get; set; }
+        public string Title { get; set; }
+        public string AuthorName { get; set; } = string.Empty;
+        public string PublisherName { get; set; } = string.Empty;
+    }
+
+    public class BookAuthorDTO
+    {
+        public int Id { get; set; }
+        public string Title { get; set; }
+        public string AuthorName { get; set; } = string.Empty;
+    }
+
+    public class BookPublisherDTO
+    {
+        public int Id { get; set; }
+        public string Title { get; set; }
+        public string PublisherName { get; set; } = string.Empty;
+    }
+}
diff --git a/exercise.webapi/DTO/PublisherDTO.cs b/exercise.webapi/DTO/PublisherDTO.cs
new file mode 100644
index 0000000..2e6e868
--- /dev/null
+++ b/exercise.webapi/DTO/PublisherDTO.cs
@@ -0,0 +1,9 @@
+namespace exercise.webapi.DTO
+{
+    public class PublisherDTO
+    {
+        public int Id { get; set; }
+        public string Name { get; set; }
+        public List<BookAuthorDTO> Books { get; set; }
+    }
+}
diff --git a/exercise.webapi/Data/DataContext.cs b/exercise.webapi/Data/DataContext.cs
index b6be7a9..3b3828f 100644
--- a/exercise.webapi/Data/DataContext.cs
+++ b/exercise.webapi/Data/DataContext.cs
@@ -24,9 +24,11 @@ protected override void OnModelCreating(ModelBuilder modelBuilder)
 
             modelBuilder.Entity<Author>().HasData(seeder.Authors);
             modelBuilder.Entity<Book>().HasData(seeder.Books);
+            modelBuilder.Entity<Publisher>().HasData(seeder.Publishers);
 
         }
         public DbSet<Author> Authors { get; set; }
         public DbSet<Book> Books { get; set; }
+        public DbSet<Publisher> Publishers { get; set; }
     }
 }
diff --git a/exercise.webapi/Data/Seeder.cs b/exercise.webapi/Data/Seeder.cs
index 955e3c8..4184fdb 100644
--- a/exercise.webapi/Data/Seeder.cs
+++ b/exercise.webapi/Data/Seeder.cs
@@ -76,17 +76,35 @@ public class Seeder
             "Flowers",
             "Leopards"
         };
+        private List<string> _publishernames = new List<string>()
+        {
+            "Penguin Random House",
+            "Hacette Livre",
+            "Harper Collins",
+            "Simon and Schuster",
+            "Macmillan Publishers",
+            "Chronicle Books",
+            "Persea Books"
+        };
 
         private List<Author> _authors = new List<Author>();
         private List<Book> _books = new List<Book>();
+        private List<Publisher> _publishers = new List<Publisher>();
 
         public Seeder()
         {
 
             Random authorRandom = new Random();
             Random bookRandom = new Random();
+            Random publisherRandom = new Random();
 
-
+            for (int y = 1; y < _publishernames.Count; y++)
+            {
+                Publisher publisher = new Publisher();
+                publisher.Id = y;
+                publisher.Name = _publishernames[y];
+                _publishers.Add(publisher);
+            }
 
             for (int x = 1; x < 250; x++)
             {
@@ -106,12 +124,13 @@ public Seeder()
                 book.Title = $"{_firstword[bookRandom.Next(_firstword.Count)]} {_secondword[bookRandom.Next(_secondword.Count)]} {_thirdword[bookRandom.Next(_thirdword.Count)]}";
                 book.AuthorId = _authors[authorRandom.Next(_authors.Count)].Id;
                 //book.Author = authors[book.AuthorId-1];
+                book.PublisherId = _publishers[publisherRandom.Next(_publishers.Count)].Id;
                 _books.Add(book);
             }
 
-
         }
         public List<Author> Authors { get { return _authors; } }
         public List<Book> Books { get { return _books; } }
+        public List<Publisher> Publishers { get { return _publishers; } }
     }
 }
diff --git a/exercise.webapi/Endpoints/AuthorApi.cs b/exercise.webapi/Endpoints/AuthorApi.cs
new file mode 100644
index 0000000..067c65c
--- /dev/null
+++ b/exercise.webapi/Endpoints/AuthorApi.cs
@@ -0,0 +1,78 @@
+using exercise.webapi.DTO;
+using exercise.webapi.Models;
+using exercise.webapi.Repository;
+using Microsoft.AspNetCore.Mvc;
+
+namespace exercise.webapi.Endpoints
+{
+    public static class AuthorApi
+    {
+        public static void ConfigureAuthorsApi(this WebApplication app)
+        {
+            var author = app.MapGroup("authors");
+            author.MapGet("/", GetAuthors);
+            author.MapGet("/{id}", GetAuthor);
+        }
+
+        [ProducesResponseType(StatusCodes.Status200OK)]
+        private static async Task<IResult> GetAuthor(IAuthorRepository authorRepository, int id)
+        {
+            var author = await authorRepository.GetAuthor(id);
+            var result = new AuthorDTO()
+            {
+                Id = author.Id,
+                FirstName = author.FirstName,
+                LastName = author.LastName,
+                Email = author.Email,  
+                Books = []
+            };
+
+            foreach (var b in author.Books)
+            {
+                BookPublisherDTO bookDTO = new BookPublisherDTO()
+                {
+                    Id = b.Id,
+                    Title = b.Title,
+                    PublisherName = b.Publisher.Name
+                };
+                result.Books.Add(bookDTO);
+            }
+
+            return TypedResults.Ok(result);
+        }
+
+        [ProducesResponseType(StatusCodes.Status200OK)]
+        private static async Task<IResult> GetAuthors(IAuthorRepository authorRepository)
+        {
+            var authors = await authorRepository.GetAllAuthors();
+            var result = new List<AuthorDTO>();
+
+            foreach (var a in authors)
+            {
+                var authorDTO = new AuthorDTO()
+                {
+                    Id = a.Id,
+                    FirstName = a.FirstName,
+                    LastName = a.LastName,
+                    Email = a.Email,
+                    Books = []
+                };
+
+                foreach(var b in a.Books)
+                {
+                    BookPublisherDTO bookDTO = new BookPublisherDTO()
+                    {
+                        Id = b.Id,
+                        Title = b.Title,
+                        PublisherName = b.Publisher.Name
+                    };
+                    authorDTO.Books.Add(bookDTO);
+                }
+                result.Add(authorDTO);
+            }
+
+            return TypedResults.Ok(result);
+        }
+
+    }
+}
diff --git a/exercise.webapi/Endpoints/BookApi.cs b/exercise.webapi/Endpoints/BookApi.cs
index 6758215..7b0ef0a 100644
--- a/exercise.webapi/Endpoints/BookApi.cs
+++ b/exercise.webapi/Endpoints/BookApi.cs
@@ -1,5 +1,9 @@
-using exercise.webapi.Models;
+using System.Collections.Immutable;
+using exercise.webapi.DTO;
+using exercise.webapi.Models;
 using exercise.webapi.Repository;
+using exercise.webapi.ViewModel;
+using Microsoft.AspNetCore.Mvc;
 using static System.Reflection.Metadata.BlobBuilder;
 
 namespace exercise.webapi.Endpoints
@@ -8,13 +12,137 @@ public static class BookApi
     {
         public static void ConfigureBooksApi(this WebApplication app)
         {
-            app.MapGet("/books", GetBooks);
+            var book = app.MapGroup("books");
+            book.MapGet("/", GetBooks);
+            book.MapGet("/{id}", GetBook);
+            book.MapPut("/{id}", UpdateBook);
+            book.MapDelete("/{id}", DeleteBook);
+            book.MapPost("/{id}", CreateBook);
         }
 
+        [ProducesResponseType(StatusCodes.Status200OK)]
+        private static async Task<IResult> GetBook(IBookRepository bookRepository, int id)
+        {
+            var book = await bookRepository.GetBook(id);
+            var result = new BookDTO()
+            {
+                Id = book.Id,
+                Title = book.Title,
+                AuthorName = $"{book.Author.FirstName} {book.Author.LastName}",
+                PublisherName = book.Publisher.Name
+            };
+
+            return TypedResults.Ok(result);
+        }
+
+        [ProducesResponseType(StatusCodes.Status200OK)]
         private static async Task<IResult> GetBooks(IBookRepository bookRepository)
         {
             var books = await bookRepository.GetAllBooks();
-            return TypedResults.Ok(books);
+            var result = new List<BookDTO>();
+
+            foreach (var b in books)
+            {
+                var book = new BookDTO()
+                {
+                    Id = b.Id,
+                    Title = b.Title,
+                    AuthorName = $"{b.Author.FirstName} {b.Author.LastName}",
+                    PublisherName = b.Publisher.Name
+                };
+                result.Add(book);
+
+            }
+
+            return TypedResults.Ok(result);
+        }
+
+        [ProducesResponseType(StatusCodes.Status200OK)]
+        private static async Task<IResult> UpdateBook(IBookRepository bookRepository, int id, BookPut model)
+        {
+            try
+            {
+                var target = await bookRepository.GetBook(id);
+                if (model.AuthorId != null) target.AuthorId = (int)model.AuthorId;
+                if (model.PublisherId != null) target.PublisherId = (int)model.PublisherId;
+
+                await bookRepository.UpdateBook(target);
+                var update = await bookRepository.GetBook(id);
+                var result = new BookDTO()
+                {
+                    Id = update.Id,
+                    Title = update.Title,
+                    AuthorName = $"{update.Author.FirstName} {update.Author.LastName}",
+                    PublisherName = update.Publisher.Name
+                };
+
+                return TypedResults.Ok(result);
+            }
+            catch (Exception ex)
+            {
+                return TypedResults.Problem(ex.Message);
+            }
+        }
+
+        [ProducesResponseType(StatusCodes.Status200OK)]
+        [ProducesResponseType(StatusCodes.Status404NotFound)]
+        private static async Task<IResult> DeleteBook(IBookRepository bookRepository, int id)
+        {
+            try
+            {
+                var target = await bookRepository.GetBook(id);
+                if (target == null) return TypedResults.NotFound("Book not found.");
+                if (bookRepository.DeleteBook(id) != null)
+                {
+                    var result = new BookDTO()
+                    {
+                        Id = target.Id,
+                        Title = target.Title,
+                        AuthorName = $"{target.Author.FirstName} {target.Author.LastName}",
+                        PublisherName = target.Publisher.Name
+                    };
+                    return TypedResults.Ok(result);
+                }
+                return TypedResults.NotFound("Book not found.");
+            }
+            catch (Exception ex)
+            {
+                return TypedResults.Problem(ex.Message);
+            }
         }
+
+        [ProducesResponseType(StatusCodes.Status200OK)]
+        private static async Task<IResult> CreateBook(IBookRepository bookRepository, IAuthorRepository authorRepository, IPublisherRepository publisherRepository, BookPost model)
+        {
+            try
+            {
+                if (string.IsNullOrEmpty(model.Title)) return TypedResults.BadRequest("Title is required.");
+                if (model.AuthorId <= 0) return TypedResults.BadRequest("Valid AuthorId is required.");
+                if (model.PublisherId <= 0) return TypedResults.BadRequest("Valid PublisherId is required.");
+               
+                var author = await authorRepository.GetAuthor(model.AuthorId);
+                if (author == null) return TypedResults.NotFound("Author does not exist in database");
+                var publisher = await publisherRepository.GetPublisher(model.PublisherId);
+                if (publisher == null) return TypedResults.NotFound("Publiser does not exist in database");
+
+                var newBook = await bookRepository.CreateBook(new Book(){ Title = model.Title, AuthorId = model.AuthorId, PublisherId = model.PublisherId});
+
+                var createdBook = await bookRepository.GetBook(newBook.Id);
+
+                BookDTO result = new BookDTO()
+                {
+                    Id = createdBook.Id,
+                    Title = createdBook.Title,
+                    AuthorName = $"{createdBook.Author.FirstName} {createdBook.Author.LastName}",
+                    PublisherName = createdBook.Publisher.Name
+                };
+                return TypedResults.Created($"/{createdBook.Id}", result);
+            }
+            catch (Exception ex)
+            {
+                return TypedResults.Problem(ex.Message);
+            }
+        }
+
     }
 }
diff --git a/exercise.webapi/Endpoints/PublisherApi.cs b/exercise.webapi/Endpoints/PublisherApi.cs
new file mode 100644
index 0000000..1927598
--- /dev/null
+++ b/exercise.webapi/Endpoints/PublisherApi.cs
@@ -0,0 +1,76 @@
+using exercise.webapi.DTO;
+using exercise.webapi.Repository;
+using Microsoft.AspNetCore.Mvc;
+
+namespace exercise.webapi.Endpoints
+{
+    public static class PublisherApi
+    {
+        
+        public static void ConfigurePublishersApi(this WebApplication app)
+        {
+            var publisher = app.MapGroup("publishers");
+            publisher.MapGet("/", GetPublishers);
+            publisher.MapGet("/{id}", GetPublisher);
+        }
+
+        [ProducesResponseType(StatusCodes.Status200OK)]
+        private static async Task<IResult> GetPublisher(IPublisherRepository publisherRepository, int id)
+        {
+            var publisher = await publisherRepository.GetPublisher(id);
+            var result = new PublisherDTO()
+            {
+                Id = publisher.Id,
+                Name = publisher.Name,
+                Books = []
+            };
+
+            foreach (var b in publisher.Books)
+            {
+                BookAuthorDTO bookDTO = new BookAuthorDTO()
+                {
+                    Id = b.Id,
+                    Title = b.Title,
+                    AuthorName = $"{b.Author.FirstName} {b.Author.LastName}",
+                };
+                result.Books.Add(bookDTO);
+            }
+
+            return TypedResults.Ok(result);
+        }
+
+        [ProducesResponseType(StatusCodes.Status200OK)]
+        private static async Task<IResult> GetPublishers(IPublisherRepository publisherRepository)
+        {
+            var publishers = await publisherRepository.GetAllPublishers();
+            var result = new List<PublisherDTO>();
+
+            foreach (var p in publishers)
+            {
+                var publisherDTO = new PublisherDTO()
+                {
+                    Id = p.Id,
+                    Name = p.Name,
+                    Books = []
+                };
+
+                foreach (var b in p.Books)
+                {
+                    if (!p.Books.Any()) continue;
+                    BookAuthorDTO bookDTO = new BookAuthorDTO()
+                    {
+                        Id = b.Id,
+                        Title = b.Title,
+                        AuthorName = $"{b.Author.FirstName} {b.Author.LastName}",
+                    };
+                    publisherDTO.Books.Add(bookDTO);
+                }
+                result.Add(publisherDTO);
+            }
+
+            return TypedResults.Ok(result);
+        }
+
+    }
+}
+
diff --git a/exercise.webapi/Models/Author.cs b/exercise.webapi/Models/Author.cs
index 9f47878..6da6f42 100644
--- a/exercise.webapi/Models/Author.cs
+++ b/exercise.webapi/Models/Author.cs
@@ -8,8 +8,6 @@ public class Author
         public string FirstName { get; set; }
         public string LastName { get; set; }
         public string Email { get; set; }
-
-        [JsonIgnore] // Todo: replace this with DTO approach
         public ICollection<Book> Books { get; set; } = new List<Book>();
     }
 }
diff --git a/exercise.webapi/Models/Book.cs b/exercise.webapi/Models/Book.cs
index 9534929..e07d178 100644
--- a/exercise.webapi/Models/Book.cs
+++ b/exercise.webapi/Models/Book.cs
@@ -6,8 +6,10 @@ public class Book
     {
         public int Id { get; set; }
         public string Title { get; set; }
-        
         public int AuthorId { get; set; }
         public Author Author { get; set; }
+
+        public int PublisherId { get; set; }
+        public Publisher Publisher { get; set; }
     }
 }
diff --git a/exercise.webapi/Models/Publisher.cs b/exercise.webapi/Models/Publisher.cs
new file mode 100644
index 0000000..98a7276
--- /dev/null
+++ b/exercise.webapi/Models/Publisher.cs
@@ -0,0 +1,9 @@
+namespace exercise.webapi.Models
+{
+    public class Publisher
+    {
+        public int Id { get; set; }
+        public string Name { get; set; }
+        public ICollection<Book> Books { get; set; } = new List<Book>();
+    }
+}
diff --git a/exercise.webapi/Program.cs b/exercise.webapi/Program.cs
index 43dec56..5fdb7b7 100644
--- a/exercise.webapi/Program.cs
+++ b/exercise.webapi/Program.cs
@@ -11,6 +11,9 @@
 builder.Services.AddSwaggerGen();
 builder.Services.AddDbContext<DataContext>(opt => opt.UseInMemoryDatabase("Library"));
 builder.Services.AddScoped<IBookRepository, BookRepository>();
+builder.Services.AddScoped<IAuthorRepository, AuthorRepository>();
+builder.Services.AddScoped<IPublisherRepository, PublisherRepository>();
+
 
 var app = builder.Build();
 
@@ -29,4 +32,6 @@
 
 app.UseHttpsRedirection();
 app.ConfigureBooksApi();
+app.ConfigureAuthorsApi();
+app.ConfigurePublishersApi();
 app.Run();
diff --git a/exercise.webapi/Repository/AuthorRepository.cs b/exercise.webapi/Repository/AuthorRepository.cs
new file mode 100644
index 0000000..8dd92a5
--- /dev/null
+++ b/exercise.webapi/Repository/AuthorRepository.cs
@@ -0,0 +1,24 @@
+using exercise.webapi.Data;
+using exercise.webapi.Models;
+using Microsoft.EntityFrameworkCore;
+
+namespace exercise.webapi.Repository
+{
+    public class AuthorRepository : IAuthorRepository
+    {
+        DataContext _db;
+
+        public AuthorRepository(DataContext db)
+        {
+            _db = db;
+        }
+        public async Task<IEnumerable<Author>> GetAllAuthors()
+        {
+            return await _db.Authors.Include(a => a.Books).ThenInclude(b => b.Publisher).ToListAsync();
+        }
+        public async Task<Author> GetAuthor(int id)
+        {
+            return await _db.Authors.Include(a => a.Books).ThenInclude(b => b.Publisher).FirstOrDefaultAsync(a => a.Id == id);
+        }
+    }
+}
diff --git a/exercise.webapi/Repository/BookRepository.cs b/exercise.webapi/Repository/BookRepository.cs
index 1f5e64a..9ea9bc5 100644
--- a/exercise.webapi/Repository/BookRepository.cs
+++ b/exercise.webapi/Repository/BookRepository.cs
@@ -15,8 +15,34 @@ public BookRepository(DataContext db)
 
         public async Task<IEnumerable<Book>> GetAllBooks()
         {
-            return await _db.Books.Include(b => b.Author).ToListAsync();
+            return await _db.Books.Include(b => b.Author).Include(b => b.Publisher).ToListAsync();
 
         }
+
+        public async Task<Book> GetBook(int id)
+        {
+            return await _db.Books.Include(b => b.Author).Include(b => b.Publisher).FirstOrDefaultAsync(b => b.Id == id);
+        }
+
+        public async Task<Book> UpdateBook(Book entity)
+        {
+            _db.Books.Attach(entity);
+            _db.Entry(entity).State = EntityState.Modified;
+            await _db.SaveChangesAsync();
+            return entity;
+        }
+        public async Task<Book> DeleteBook(int id)
+        {
+            var target = await _db.Books.FirstOrDefaultAsync(b => b.Id == id);
+            _db.Books.Remove(target);
+            _db.SaveChanges();
+            return target;
+        }
+        public async Task<Book> CreateBook(Book entity)
+        {
+            await _db.Books.AddAsync(entity);
+            await _db.SaveChangesAsync();
+            return entity;
+        }
     }
 }
diff --git a/exercise.webapi/Repository/IAuthorRepository.cs b/exercise.webapi/Repository/IAuthorRepository.cs
new file mode 100644
index 0000000..9dfd1ef
--- /dev/null
+++ b/exercise.webapi/Repository/IAuthorRepository.cs
@@ -0,0 +1,10 @@
+using exercise.webapi.Models;
+
+namespace exercise.webapi.Repository
+{
+    public interface IAuthorRepository
+    {
+        Task<Author> GetAuthor(int id);
+        Task<IEnumerable<Author>> GetAllAuthors();
+    }
+}
diff --git a/exercise.webapi/Repository/IBookRepository.cs b/exercise.webapi/Repository/IBookRepository.cs
index f860016..c442e30 100644
--- a/exercise.webapi/Repository/IBookRepository.cs
+++ b/exercise.webapi/Repository/IBookRepository.cs
@@ -5,5 +5,9 @@ namespace exercise.webapi.Repository
     public interface IBookRepository
     {
         public Task<IEnumerable<Book>> GetAllBooks();
+        public Task<Book> GetBook(int id);
+        public Task<Book> UpdateBook(Book entity);
+        public Task<Book> DeleteBook(int id);
+        public Task<Book> CreateBook(Book entity);
     }
 }
diff --git a/exercise.webapi/Repository/IPublisherRepository.cs b/exercise.webapi/Repository/IPublisherRepository.cs
new file mode 100644
index 0000000..32a1aab
--- /dev/null
+++ b/exercise.webapi/Repository/IPublisherRepository.cs
@@ -0,0 +1,10 @@
+using exercise.webapi.Models;
+
+namespace exercise.webapi.Repository
+{
+    public interface IPublisherRepository
+    {
+        Task<Publisher> GetPublisher(int id);
+        Task<IEnumerable<Publisher>> GetAllPublishers();
+    }
+}
diff --git a/exercise.webapi/Repository/PublisherRepository.cs b/exercise.webapi/Repository/PublisherRepository.cs
new file mode 100644
index 0000000..da00a36
--- /dev/null
+++ b/exercise.webapi/Repository/PublisherRepository.cs
@@ -0,0 +1,24 @@
+using exercise.webapi.Data;
+using exercise.webapi.Models;
+using Microsoft.EntityFrameworkCore;
+
+namespace exercise.webapi.Repository
+{
+    public class PublisherRepository : IPublisherRepository
+    {
+        DataContext _db;
+
+        public PublisherRepository(DataContext db)
+        {
+            _db = db;
+        }
+        public async Task<IEnumerable<Publisher>> GetAllPublishers()
+        {
+            return await _db.Publishers.Include(p => p.Books).ThenInclude(b => b.Author).ToListAsync();
+        }
+        public async Task<Publisher> GetPublisher(int id)
+        {
+            return await _db.Publishers.Include(p => p.Books).ThenInclude(b => b.Author).FirstOrDefaultAsync(a => a.Id == id);
+        }
+    }
+}
diff --git a/exercise.webapi/ViewModel/BookPost.cs b/exercise.webapi/ViewModel/BookPost.cs
new file mode 100644
index 0000000..169fd09
--- /dev/null
+++ b/exercise.webapi/ViewModel/BookPost.cs
@@ -0,0 +1,9 @@
+namespace exercise.webapi.ViewModel
+{
+    public class BookPost
+    {
+        public string Title { get; set; }
+        public int AuthorId { get; set; }
+        public int PublisherId { get; set; }
+    }
+}
diff --git a/exercise.webapi/ViewModel/BookPut.cs b/exercise.webapi/ViewModel/BookPut.cs
new file mode 100644
index 0000000..33b34f7
--- /dev/null
+++ b/exercise.webapi/ViewModel/BookPut.cs
@@ -0,0 +1,10 @@
+using exercise.webapi.Models;
+
+namespace exercise.webapi.ViewModel
+{
+    public class BookPut
+    {
+        public int? AuthorId { get; set; }
+        public int? PublisherId { get; set; }
+    }
+}
diff --git a/exercise.webapi/exercise.webapi.csproj b/exercise.webapi/exercise.webapi.csproj
index 0ff4269..00b0722 100644
--- a/exercise.webapi/exercise.webapi.csproj
+++ b/exercise.webapi/exercise.webapi.csproj
@@ -9,6 +9,11 @@
 
   <ItemGroup>
     <PackageReference Include="Microsoft.AspNetCore.OpenApi" Version="8.0.0" />
+    <PackageReference Include="Microsoft.EntityFrameworkCore" Version="9.0.1" />
+    <PackageReference Include="Microsoft.EntityFrameworkCore.Design" Version="9.0.1">
+      <PrivateAssets>all</PrivateAssets>
+      <IncludeAssets>runtime; build; native; contentfiles; analyzers; buildtransitive</IncludeAssets>
+    </PackageReference>
     <PackageReference Include="Microsoft.EntityFrameworkCore.InMemory" Version="8.0.1" />
     <PackageReference Include="Scalar.AspNetCore" Version="2.0.4" />
     <PackageReference Include="Swashbuckle.AspNetCore" Version="6.4.0" />