Peirce and Philo
- Discusses Charles Peirce's account of conditionals, hypotheticals, and what he takes from Cicero's account of the debate between Philo and Diodorus.
- http://www.clas.ufl.edu/users/jzeman/peirce_and_philo.htm

Conditional Sentences
- Lecture notes on the analysis of condition sentences by Paul Kay.
- http://www.icsi.berkeley.edu/~kay/bcg/lec07.html

Nomic Dependencies & Contrary-to-fact Conditionals
- Essay by William S. Boardman discussing Fred Dretske's measles examples in his book `Knowledge and the Flow of Information'.
- http://www.lawrence.edu/fac/boardmaw/contr_cond_nomic.html

Faithful and Fruitful Logic
- Article by John Howes, presented at the 20th World Congress of Philosophy.
- http://www.bu.edu/wcp/Papers/Logi/LogiHowe.htm

Relevance Logic
- Article in the Stanford Encyclopaedia of Philosophy, by Edwin Mares.
- http://plato.stanford.edu/entries/logic-relevance/

Paradoxes of Material Implication
- Lecture notes by Peter Suber.
- http://www.earlham.edu/~peters/courses/log/mat-imp.htm