TY  - BOOK
AU  - Penfold,R.A.
AU  - Penfold,J.W.
TI  - An introduction to QL machine code
SN  - 0859341313
U1  - QA/76.8.S625 
PY  - 1985///
CY  - Shepherds Bush road, London
PB  - Bernard Babani Pub. Ltd.
KW  - Sinclair QL (Computer) -- Programming.
ER  -