publisher: Open University Press publish date: April 28th 1989
format: hardcover pages: 256
language: English
ISBN:
0335158765 (9780335158768)
publisher: Open University Press publish date: May 28th 1991
format: paperback pages: 224
language: English
ISBN:
0335097952 (9780335097951)
publisher: Open University Press publish date: June 1st 1992
format: paperback pages: 244
language: English
ISBN:
0335157564 (9780335157563)