Ruby:
David A. Black - <i>The Well-Grounded Rubyist</i> - <a href="http:&#x2F;&#x2F;www.amazon.com&#x2F;Well-Grounded-Rubyist-David-Black&#x2F;dp&#x2F;1617291692&#x2F;" rel="nofollow">http:&#x2F;&#x2F;www.amazon.com&#x2F;Well-Grounded-Rubyist-David-Black&#x2F;dp&#x2F;1...</a><p>Great both for people new to the language and those looking to strengthen their foundations.