Popular Science Magazine Vintage November 1969

Popular Science Magazine Vintage July 1969, TRI-DYNE ENGINE, MARS UP CLOSE!

Popular Science Magazine December 1969

Popular Science Magazine Vintage December 1967

Popular Science Magazine December 1969 Piston-Powered Engine ML 070117nonjhe

GALAXY SCIENCE FICTION Magazine December 1969

POPULAR SCIENCE Magazine, DECEMBER 1969, PISTON-POWERED ROTARY ENGINE, CITROEN!

Popular Hot Rodding Magazine December 1969