M & R Laboratories
Columbus, Ohio

M & R Publications
Turlock, CA

M & R Pubns

M R K Publishing
Petaluma, CA

M&R Enterprises
Ketchum, ID

M-R-K Pub
Petaluma, Calif

M-R-K Publishing
Petaluma, Calif

M. R. Sainty & K. A. Johnson
Sydney

M. R. Stallion
Braintree

M. Raber
Medicine Hat, AB

M. Rafferty
[Toowoomba, Qld.]

M. Rendel
Wellington

M. Resnick
[S.l.]

M. Reynolds
Toronto

M. Rieger
München

M. Riley
[Calif.?]

M. Roberts
Morven, Qld

M. Robertson
[London]

M. Robertson in association with the Open University
Oxford

M. Robertson, in association with Fontana/Collins
London