@ -2294,7 +2294,6 @@ Kerridge (PDF) (email address *requested*, not required)
* [Exploratory Data Analysis with R ](https://leanpub.com/exdata ) - Roger D. Peng *(Leanpub account or valid email requested)*
* [Introduction to Probability and Statistics Using R ](https://github.com/gjkerns/IPSUR ) - G. Jay Kerns (PDF)
* [Learning Statistics with R ](https://web.archive.org/web/20170625184412/http://health.adelaide.edu.au/psychology/ccs/teaching/lsr/ ) - Daniel Navarro
* [Machine Learning with R ](https://www.packtpub.com/packt/free-ebook/r-machine-learning ) - Brett Lantz, Packt. (email address *requested* , not required)
* [ModernDive ](https://ismayc.github.io/moderndiver-book/ ) - Chester Ismay and Albert Y. Kim
* [Practical Regression and Anova using R ](http://cran.r-project.org/doc/contrib/Faraway-PRA.pdf ) - Julian J. Faraway (PDF)
* [R for Data Science ](http://r4ds.had.co.nz ) - Garrett Grolemund and Hadley Wickham
@ -2314,14 +2313,13 @@ Kerridge (PDF) (email address *requested*, not required)
### Racket
* [How to Design Programs 2e ](http://www.ccs.neu.edu/home/matthias/HtDP2e/ )
* [How to Design Programs ](https://htdp.org/2019-02-24/ ) - Matthias Felleisen, Robert Bruce Findler, Matthew Flatt, Shriram Krishnamurthi
* [Programming Languages: Application and Interpretation ](http://cs.brown.edu/courses/cs173/2012/book/index.html )
* [The Racket Guide ](http://docs.racket-lang.org/guide/index.html )
### Raspberry Pi
* [Raspberry Pi Cookbook for Python Programmers ](https://www.packtpub.com/packt/free-ebook/python-raspberry-pi-cookbook ) - Tim Cox, Packt. (PDF) (email address *requested* , not required)
* [Raspberry Pi: Measure, Record, Explore ](https://leanpub.com/RPiMRE/read ) - Malcolm Maclean (HTML)
* [Raspberry Pi Users Guide - (2012) ](http://www.cs.unca.edu/~bruce/Fall14/360/RPiUsersGuide.pdf ) - Eben Upton (PDF)
* [The Official Raspberry Pi Project Book ](https://www.raspberrypi.org/magpi-issues/Projects_Book_v1.pdf ) (PDF)
@ -2343,7 +2341,7 @@ Kerridge (PDF) (email address *requested*, not required)
* [Learn Ruby First ](https://essenceofchaos.gitbooks.io/learn-ruby-first/content/ ) - Frederick John
* [Learn Ruby the Hard Way ](http://learnrubythehardway.org/book/ ) - Zed Shaw
* [Learn to Program ](http://pine.fm/LearnToProgram/ ) - Chris Pine
* [Mr. Neighborly's Humble Little Ruby Book ](http://www.humblelittlerubybook.com )
* [Mr. Neighborly's Humble Little Ruby Book ](https://web.archive.org/web/20180321101922/http ://www.humblelittlerubybook.com/book/html/index.html )
* [Object Oriented Programming with Ruby ](https://launchschool.com/books/oo_ruby ) - Launch School
* [Practicing Ruby ](https://github.com/elm-city-craftworks/practicing-ruby-manuscripts )
* [Programming Ruby ](http://ruby-doc.com/docs/ProgrammingRuby/ )
@ -2439,7 +2437,7 @@ Kerridge (PDF) (email address *requested*, not required)
* [Exploring Lift ](http://exploring.liftweb.net ) (published earlier as "The Definitive Guide to Lift", [PDF ](http://groups.google.com/group/the-lift-book ))
* [Lift ](https://github.com/tjweir/liftbook )
* [Lift Cookbook ](http://chimera.labs.oreilly.com/books/1234000000030/index.html ) - Richard Dallaway
* [Lift Cookbook ](https://www.oreilly.com/library/view/lift-cookbook/9781449365042/ ) - Richard Dallaway
* [Simply Lift ](http://simply.liftweb.net/Simply_Lift.pdf ) - David Pollak (PDF)
@ -2454,7 +2452,6 @@ Kerridge (PDF) (email address *requested*, not required)
* [A Pamphlet Against R. Computational Intelligence in Guile Scheme ](https://panicz.github.io/pamphlet/ )
* [An Introduction to Scheme and its Implementation ](http://www.cs.rpi.edu/academics/courses/fall00/ai/scheme/reference/schintro-v14/schintro_toc.html )
* [Concrete Abstractions: An Introduction to Computer Science Using Scheme ](https://gustavus.edu/+max/concrete-abstractions.html ) - M. Hailperin, B. Kaiser, K. Knight
* [How to Design Programs ](http://htdp.org )
* [Scheme Tutorial ](http://www.cs.hut.fi/Studies/T-93.210/schemetutorial/ )
* [Simply Scheme: Introducing Computer Science ](http://www.cs.berkeley.edu/~bh/ss-toc2.html ) - B. Harvey, M. Wright
* [Teach Yourself Scheme in Fixnum Days ](https://ds26gte.github.io/tyscheme/index-Z-H-1.html )
@ -2487,12 +2484,11 @@ Kerridge (PDF) (email address *requested*, not required)
### Smalltalk
* [Deep into Pharo ](http://books.pharo.org/deep-into-pharo/ )
* [Deep into Pharo ](http://books.pharo.org/deep-into-pharo/ ) - Alexandre Bergel, Damien Cassou, Stéphane Ducasse, Jannik Laval
* [Dynamic Web Development with Seaside ](http://book.seaside.st/book/table-of-contents ) - S. Ducasse, L. Renggli, C. D. Shaffer, R. Zaccone
* [Enterprise Pharo: a Web Perspective ](http://books.pharo.org/enterprise-pharo/ )
* [Numerical Methods with Pharo ](http://books.pharo.org/numerical-methods/ )
* [Pharo by Example ](http://books.pharo.org/pharo-by-example/ ) (Smalltalk Implementation and IDE)
* [Squeak By Example ](http://www.squeakbyexample.org ) (Smalltalk Implementation and IDE)
* [Numerical Methods with Pharo ](http://books.pharo.org/numerical-methods/ ) - Didier Besset, Stéphane Ducasse, Serge Stinckwich
* [Pharo by Example ](http://books.pharo.org/pharo-by-example/ ) - Andrew P. Black et al. (Smalltalk Implementation and IDE)
* [Stef's Free Online Smalltalk Books ](http://stephane.ducasse.free.fr/FreeBooks.html ) (meta-list)
@ -2515,7 +2511,7 @@ Kerridge (PDF) (email address *requested*, not required)
### SQL (implementation agnostic)
* [Developing Time-Oriented Database Applications in SQL ](http://www.cs.arizona.edu/people/rts/publications.html )
* [Developing Time-Oriented Database Applications in SQL ](https://www2.cs.arizona.edu/~rts/tdbbook.pdf ) - Richard T. Snodgrass (PDF )
* [SQL For Web Nerds ](http://philip.greenspun.com/sql/ )
* [SQL Notes for Professionals ](http://books.goalkicker.com/SQLBook/ )
* [Use The Index, Luke!: A Guide To SQL Database Performance ](http://use-the-index-luke.com )