TY  - BOOK
ED  - American Petroleum Institute, API
TI  - Bulletin on referenced standards for committee 6, standardization of valves and wellhead equipment: API Bulletin 6RS
U1  - Caja archivo 1 
PY  - 1990///
CY  - Washington
PB  - American Petroleum Institute, API
KW  - Normas API
KW  - Normalización
ER  -