*[ Glenn's English Wikipedia page]
*[ Glenns danske Wikipedia side]
==Useful addresses==
*[ The Classic Maya Calendar and Day Numbering System] Quote: "...The Maya system uses only three symbols for zero (a shell-shaped glyph)..."
**[ Ciphers and Civilizations By Blair Moffett] Quote: "...The Hindus are also the only older people besides the Mayans who are known to have employed the concept of zero in their mathematics. In fact, our culture obtained the zero only because Arab scholars in Bagdad in the seventh century AD translated a Hindu text on astronomy and thus rediscovered the zero..."