TY  - BOOK
AU  - Black,William Murray
ED  - U.S. Army Engineer School.
TI  - Pamphlet on the evolution of the art of fortification
T2  - Occasional papers, Engineer school, U.S. army,
AV  - UG1 .U5 no. 58
PY  - 1919///
CY  - Washington
PB  - Govt. print. off.
KW  - Fortification
ER  -