Update README.md

Author: Faares

README.md

@@ -22,6 +22,7 @@ As the title says! recently, I become deep into special areas, and references be
     - [Analytic Number Theory](#analytic-number-theory)
     - [Algebraic Number Theory](#algebraic-number-theory)
     - [Geometric Number Theory](#geometric-number-theory)
+  - [Ring Theory](#ring-theory)
   - [Mathematical Analysis](#mathematical-analysis)
     - [Real Analysis](#real-analysis)
     - [Complex Analysis](#complex-analysis)
@@ -114,7 +115,7 @@ As the title says! recently, I become deep into special areas, and references be
 > TODO
 
 ### Ring Theory
-- *MIT Course.* From Numbers to Rings: The Early History of Ring Theory. [[Online](https://web.archive.org/web/20120722002823/http://retro.seals.ch/cntmng?type=pdf&rid=elemat-001:1998:53::22&subp=hires)] - [[PDF](https://www.ems-ph.org/journals/show_pdf.php?issn=0013-6018&vol=53&iss=1&rank=2)]
+- *Kleiner, I.* From Numbers to Rings: The Early History of Ring Theory. [[Online](https://web.archive.org/web/20120722002823/http://retro.seals.ch/cntmng?type=pdf&rid=elemat-001:1998:53::22&subp=hires)] - [[PDF](https://www.ems-ph.org/journals/show_pdf.php?issn=0013-6018&vol=53&iss=1&rank=2)]
 
 ### Mathematical Analysis
 - *Ruden, W.* Principles of Mathematical Analysis. [[Online](https://web.math.ucsb.edu/~agboola/teaching/2021/winter/122A/rudin.pdf)]