APA Citation

Penfold, R. A., & Penfold, R. A. (1982). Mini-matrix board projects. London, England: Bernard Babani.

Chicago Style Citation

Penfold, R. A., and R. A. Penfold. Mini-matrix Board Projects. London, England: Bernard Babani, 1982.

MLA Citation

Penfold, R. A., and R. A. Penfold. Mini-matrix Board Projects. London, England: Bernard Babani, 1982.

Warning: These citations may not always be 100% accurate.