###### Nature of Mathematics

- Proofs and Refutations: The Logic of Mathematical Discovery by Imre Lakatos
- A Mathematician’s Apology (Canto) by G.H. Hardy
- What is mathematics for? by Underwood Dudley
- 18 Unconventional Essays on the Nature of Mathematics
- The Best Writing on Mathematics 2010 by Mercea Pitici
- The Best Writing on Mathematics 2011by Mercea Pitici
- Euclid’s Elements (online)
- Nature of Mathematics (blog)

###### Learning Theories

- Theories of Mathematics Education: Seeking New Frontiers (Advances in Mathematics Education) by Lyn English, B. Sriraman
- Theories of Learning (site) classified according major theories
- Index of learning theories (site)
- Learning-Theories (blog)
- Skemp

###### Teaching Mathematics

- Anna Sierpinska’s Lecture Notes – theory of didactical situation
- What counts as Mathematical Discourse

###### Research

1. Critical Guidelines for Peer Reviewers