Teach Yourself Logic 2017: A Study Guide [pdf] (▻http://www.logicmat...
▻https://diasp.eu/p/5964863
Teach Yourself Logic 2017 : A Study Guide [pdf]
Hacker News Comments : ▻https://news.ycombinator.com/item?id=15114139
Source : ▻http://www.logicmatters.net/resources/pdfs/TeachYourselfLogic2017.pdf