TY  - BOOK
AU  - Zill, Dennis G., 
TI  - Differential equations with boundary-value problems / Dennis G. Zill, Michael R. Cullen.- 3rd ed
SN  - 0534931588
U1  - 515.35 ZIL 
CY  - Boston : PWS-KENT, c1993.
KW  - Differential equations
ER  -