TY  - BOOK
AU  - Allenby, R.B.J.T.
AU  - Slomson, Alan
TI  - How to count : : an introduction to combinatorics 
T2  - Discrete mathematics and its applications
SN  - 9781420082609
U1  - 511.6 
PY  - 2011///
CY  - Boca Raton
PB  - CRC Press
ER  -