TY  - BOOK
AU  - _David E. Penney 
TI  - Elementary Differential Equations with Boundary Value Problems/ 
AV  - QA 371 .E33 1992  
PY  - 1992///.
CY  - New Jersey
PB  -  Prentice Hall, 
KW  - _Differential equations.
N1  - includes index
ER  -