Herbert William Mullin early 1970's Santa Cruz, CA serial killer.

9" x 12" acrylic painting signed on the front, Mullin.
He has written, dated and signed again on the back, Herbert Wm. Mullin March 8, 2004 Monday. Cubic volume of earth - surface area of earth - approximations using solid geometry formulas.

Herbert Mullin Geometry Painting Signed Twice