Standards:
RIJNDAEL:
http://csrc.nist.gov/CryptoToolkit/aes/rijndael/
http://csrc.nist.gov/archive/aes/rijndael/Rijndael-ammended.pdf
SHA2:
http://csrc.nist.gov/publications/fips/fips180-2/fips180-2withchangenotice.pdf
LUHN:
http://en.wikipedia.org/wiki/Luhn
ArpanTECH