Math Websites

• Sharif OCW
• LAG
• GDZ
• Numdam
• seals
• emani
• Kolekcja Matematyczna
• Gallica-Math
• mini-DML
• RBSM
• Jahrbuch
• DML-CZ

Dictionaries

• Steingass Dictionary

Programs and Softwares

• Pdftk is a tool for manipulating PDF files.
• Detexify is a very interesting online tool, when you want to use a LaTeX symbol, but you don't recall its name!