TY  - BOOK
TI  - Breakthrough to math: subtracting whole numbers, level 1, book 3 worksheet 
SN  - 0-88336-812-9
AV  - TR(GS 510.7 BRE L1
PY  - 1978///
CY  - Syracuse, NY
PB  - Readers Press
KW  - Mathematics - - study and teaching
KW  - Subtraction
ER  -