TY  - BOOK
AU  - Lipschutz Seymour,  /Lipson Marc
TI  - Theory and Problems of discrete Mathematics
AV  - QA39.2. L5  2005 
PY  - 2007///
CY  - Boston 
PB  - McGraw Hill
KW  - Algebra,  Homological
KW  - Group theory
KW  - Dimension theory (Algebra)
ER  -