Update books' editions

* Updated the links for books that have a newer edition. I have included the authors' home page for the book where possible.
* Updated some titles to reflect the linked edition. I have maintained the original format (``2e`` for the books in the ``Programming`` section ``(2nd Edition)`` for the books in the other sections). Unifying the format could be something to consider.

extras/readings.md

@@ -11,16 +11,16 @@ Or, if you are struggling in one of the courses, perhaps reading a book on the s
 
 Name | Author(s)
 :-- | :--:
-[Introduction to Computation and Programming Using Python 2e](https://www.amazon.com/Introduction-Computation-Programming-Using-Python/dp/0262529629/) | John V. Guttag
+[Introduction to Computation and Programming Using Python 3e](https://mitpress.mit.edu/books/introduction-computation-and-programming-using-python-third-edition) | John V. Guttag
 [Think Python 2e](http://greenteapress.com/wp/think-python-2e/) | Allen B. Downey
-[How to Design Programs](https://www.htdp.org/) | Matthias Felleisen, Robert Bruce Findler, Matthew Flatt, Shriram Krishnamurthi
-[Structure and Interpretation of Computer Programs](https://mitpress.mit.edu/sites/default/files/sicp/full-text/book/book.html) | Hal Abelson, Jerry Sussman, Julie Sussman 
+[How to Design Programs 2e](https://www.htdp.org/) | Matthias Felleisen, Robert Bruce Findler, Matthew Flatt, Shriram Krishnamurthi
+[Structure and Interpretation of Computer Programs 2e](https://mitpress.mit.edu/sites/default/files/sicp/full-text/book/book.html) | Hal Abelson, Jerry Sussman, Julie Sussman 
 [Concepts, Techniques, and Models of Computer Programming](https://www.amazon.com/gp/product/0262220695) | Peter Van Roy, Seif Haridi
 [Design Patterns: Elements of Reusable Object-Oriented Software](https://www.amazon.com/Design-Patterns-Elements-Reusable-Object-Oriented/dp/0201633612) | Erich Gamma, Richard Helm, Ralph Johnson, John Vlissides
 [Refactoring](https://www.refactoring.com/) | Martin Fowler
 [Clean Code](https://www.amazon.com/Clean-Code-Handbook-Software-Craftsmanship/dp/0132350882) | Robert Martin
 [Code Complete 2e](https://www.amazon.com/Code-Complete-Practical-Handbook-Construction/dp/0735619670) | Steve McConnell
-[The Pragmatic Programmer](https://www.amazon.com/Pragmatic-Programmer-Journeyman-Master/dp/020161622X) | Andrew Hunt, David Thomas
+[The Pragmatic Programmer 2e](https://pragprog.com/titles/tpp20/the-pragmatic-programmer-20th-anniversary-edition/) | Andrew Hunt, David Thomas
 [Programming Languages: Application and Interpretation](http://cs.brown.edu/~sk/Publications/Books/ProgLangs/) | Shriram Krishnamurthi
 [Programming and Programming Languages](https://papl.cs.brown.edu/2018/) | Shriram Krishnamurthi, Benjamin S. Lerner, Joe Gibbs Politz
 [Competitive Programming](https://cpbook.net/) | Steven Halim, Felix Halim
@@ -35,7 +35,7 @@ Name | Author(s)
 [Discrete Mathematics: An Open Introduction](http://discrete.openmathbooks.org/dmoi/) | Oscar Levin
 [Applied Discrete Structures](http://faculty.uml.edu/klevasseur/ads2/) | Alan Doerr, Ken Levasseur
 [Grinstead and Snell’s Introduction to Probability](https://math.dartmouth.edu/~prob/prob/prob.pdf) |Charles M. Grinstead, J. Laurie Snell
-[Introduction to Linear Algebra](https://www.amazon.com/Introduction-Linear-Algebra-Gilbert-Strang/dp/0980232775/) | Gilbert Strang
+[Introduction to Linear Algebra (5th Edition)](https://math.mit.edu/~gs/linearalgebra/) | Gilbert Strang
 
 ## Systems
 
@@ -44,9 +44,9 @@ Name | Author(s)
 [But How Do It Know?](http://www.buthowdoitknow.com/) | J. Clark Scott
 [Computer Systems: A Programmer's Perspective (3rd Edition)](http://csapp.cs.cmu.edu/) | Randal E. Bryant, David R. O'Hallaron
 [Modern Operating Systems (4th Edition)](http://www.amazon.com/Modern-Operating-Systems-Andrew-Tanenbaum/dp/013359162X/) | Andrew S. Tanenbaum, Herbert Bos
-[Computer Organization and Design: The Hardware/Software Interface](https://www.amazon.com/gp/product/0124077269) | David Patternson, John Hennessy
+[Computer Organization and Design: The Hardware/Software Interface (6th Edition)](https://www.amazon.com/Computer-Organization-Design-MIPS-Architecture/dp/0128201096/) | David Patternson, John Hennessy
 [Computer Networks (5th Edition)](http://www.amazon.com/Computer-Networks-5th-Andrew-Tanenbaum/dp/0132126958/) | Andrew S. Tanenbaum, David J. Wetherall
-[Computer Networking: A Top-Down Approach (6th Edition)](https://www.amazon.com/Computer-Networking-A-Top-Down-Approach/dp/1292153598/) | James F Kurose, Keith W Ross
+[Computer Networking: A Top-Down Approach (8th Edition)](https://gaia.cs.umass.edu/kurose_ross/index.html) | James F Kurose, Keith W Ross
 [Distributed Systems: Principles and Paradigms](https://www.amazon.com/Distributed-Systems-Principles-Andrew-Tanenbaum/dp/153028175X) | Andrew Tanenbaum
 [Operating Systems Design and Implementation](https://www.amazon.com/Operating-Systems-Design-Implementation-3rd/dp/0131429388) | Andrew S. Tanenbaum, Albert S. Woodhull
 [Principles of Compiler Design](https://www.amazon.com/Principles-Compiler-Addison-Wesley-information-processing/dp/0201000229) | Alfred Aho, Jeffrey Ullman
@@ -58,9 +58,9 @@ Name | Author(s)
 Name | Author(s)
 :-- | :--:
 [Introduction to Computing: Explorations in Language, Logic, and Machines](http://www.computingbook.org/) | David Evans
-[Introduction to the Theory of Computation](https://www.amazon.com/Introduction-Theory-Computation-Michael-Sipser/dp/113318779X) | Michael Sipser
+[Introduction to the Theory of Computation (3rd Edition)](https://www.amazon.com/Introduction-Theory-Computation-Michael-Sipser/dp/113318779X) | Michael Sipser
 [Introduction to Algorithms (3rd Edition)](http://www.amazon.com/Introduction-Algorithms-3rd-MIT-Press/dp/0262033844/) | Thomas H. Cormen, Charles E. Leiserson, Ronald L. Rivest, Clifford Stein
-[The Algorithm Design Manual](https://www.amazon.com/gp/product/1848000693) | Steven Skiena
+[The Algorithm Design Manual (3rd Edition)](https://www.algorist.com/) | Steven Skiena
 [Category Theory: A Gentle Introduction](http://www.logicmatters.net/resources/pdfs/GentleIntro.pdf) | Peter Smith
 [Category Theory for Programmers: The Preface](https://bartoszmilewski.com/2014/10/28/category-theory-for-programmers-the-preface/) | Bartosz Milewski
 [An Introduction to Information Retrieval](https://nlp.stanford.edu/IR-book/pdf/irbookonlinereading.pdf) | Christopher D. Manning, Prabhakar Raghavan, Hinrich Schütze
@@ -70,10 +70,10 @@ Name | Author(s)
 Name | Author(s)
 :-- | :--:
 [Architecture of a Database System](http://db.cs.berkeley.edu/papers/fntdb07-architecture.pdf) | Joseph M. Hellerstein, Michael Stonebraker, James Hamilton
-[Readings in Database Systems](http://www.redbook.io/) | Peter Bailis, Joseph M. Hellerstein, Michael Stonebraker, editors
-[Database Management Systems](https://www.amazon.com/gp/product/0072465638) | Raghu Ramakrishnan, Johannes Gehrke
+[Readings in Database Systems (5th Edition)](http://www.redbook.io/) | Peter Bailis, Joseph M. Hellerstein, Michael Stonebraker, editors
+[Database Management Systems (3rd Edition)](https://www.amazon.com/gp/product/0072465638) | Raghu Ramakrishnan, Johannes Gehrke
 [Transaction Processing: Concepts and Techniques](https://www.amazon.com/Transaction-Processing-Concepts-Techniques-Management/dp/1558601902) | Jim Gray, Andreas Reuter
-[Data and Reality: A Timeless Perspective on Perceiving and Managing Information in Our Imprecise World](https://www.amazon.com/Data-Reality-Perspective-Perceiving-Information/dp/1935504215) | William Kent
+[Data and Reality: A Timeless Perspective on Perceiving and Managing Information in Our Imprecise World (3rd Edition)](https://www.amazon.com/Data-Reality-Perspective-Perceiving-Information/dp/1935504215) | William Kent
 [The Architecture of Open Source Applications](http://aosabook.org/en/) | Michael DiBernardo (editor)
 [An Introduction to Statistical Learning](https://www-bcf.usc.edu/~gareth/ISL/) |  Gareth James, Daniela Witten, Trevor Hastie and Robert Tibshirani
 [Deep Learning](http://www.deeplearningbook.org/) | Ian Goodfellow, Yoshua Bengio and Aaron Courville