diff --git a/docs/fode.rst b/docs/fode.rst
index 0df0a1b..b78a3b9 100644
--- a/docs/fode.rst
+++ b/docs/fode.rst
@@ -8,10 +8,15 @@ Single-Term Fractional Ordinary Differential Equations
 History Handling
 ----------------
 
-.. autoclass:: StateHistory
-.. autoclass:: SourceHistory
+.. autoclass:: State
 .. autoclass:: History
 
+.. autoclass:: ProductIntegrationState
+.. autoclass:: VariableProductIntegrationHistory
+
+.. autoclass:: FixedState
+.. autoclass:: FixedSizeHistory
+
 Interface
 ---------
 
@@ -20,10 +25,11 @@ Interface
 .. autoclass:: StepCompleted
 
 .. autoclass:: FractionalDifferentialEquationMethod
+.. autoclass:: ProductIntegrationMethod
 
-.. autofunction:: make_initial_condition
 .. autofunction:: evolve
 .. autofunction:: advance
+.. autofunction:: make_initial_condition
 
 .. autofunction:: make_predict_time_step_fixed
 .. autofunction:: make_predict_time_step_graded
@@ -31,7 +37,8 @@ Interface
 Caputo Derivative FODEs
 =======================
 
-.. autoclass:: CaputoDifferentialEquationMethod
+.. autoclass:: CaputoProductIntegrationMethod
+
 .. autoclass:: CaputoForwardEulerMethod
 .. autoclass:: CaputoWeightedEulerMethod
 .. autoclass:: CaputoPredictorCorrectorMethod
diff --git a/docs/misc.rst b/docs/misc.rst
index 1c12d9d..dbfe243 100644
--- a/docs/misc.rst
+++ b/docs/misc.rst
@@ -16,6 +16,11 @@ Jacobi Polynomials
 
 .. automodule:: pycaputo.jacobi
 
+Generating Functions
+--------------------
+
+.. automodule:: pycaputo.generating_functions
+
 Logging
 -------
 
diff --git a/pycaputo/derivatives.py b/pycaputo/derivatives.py
index d4f361b..29bc608 100644
--- a/pycaputo/derivatives.py
+++ b/pycaputo/derivatives.py
@@ -28,8 +28,8 @@ class FractionalOperator:
     """
 
     #: Order of the fractional operator, as real number
-    # :math:`\alpha \in \mathbb{R}`. A positive number would denote a derivative,
-    # while a negative number would denote a fractional integral instead.
+    #: :math:`\alpha \in \mathbb{R}`. A positive number would denote a derivative,
+    #: while a negative number would denote a fractional integral instead.
     order: float
 
     @property
diff --git a/pycaputo/fode/__init__.py b/pycaputo/fode/__init__.py
index 15a1675..c7492c7 100644
--- a/pycaputo/fode/__init__.py
+++ b/pycaputo/fode/__init__.py
@@ -22,6 +22,7 @@
 )
 from pycaputo.fode.history import (
     FixedSizeHistory,
+    FixedState,
     History,
     ProductIntegrationState,
     State,
@@ -43,6 +44,7 @@
     "CaputoWeightedEulerMethod",
     "Event",
     "FixedSizeHistory",
+    "FixedState",
     "FractionalDifferentialEquationMethod",
     "History",
     "ProductIntegrationMethod",
diff --git a/pycaputo/fode/history.py b/pycaputo/fode/history.py
index 40a7810..4bbd697 100644
--- a/pycaputo/fode/history.py
+++ b/pycaputo/fode/history.py
@@ -47,7 +47,7 @@ def __len__(self) -> int:
     @abstractmethod
     def __getitem__(self, k: int) -> State:
         """
-        :returns: a :class:`StateHistory` from the *k*-th checkpoint.
+        :returns: a compound :class:`State` from the *k*-th checkpoint.
         """
 
     @abstractmethod