Dimetrodon by Fumiaki Kawahata

Diagrams in NOA Magazine 183
Diagrams in Origami Dinosaurs Premium by Makoto Yamaguchi
Diagrams in Origami Fantasy by Fumiaki Kawahata
Diagrams in Origami USA Convention 1992
Folded from a square of "dinosaur" paper

Dimetrodon by Robert J. Lang

Diagrams in The Complete Book of Origami by Robert J. Lang
Folded from a square of Japanese Foil

Dimetrodon by Yamada Katsuhisa

Diagrams in Origami Dinosaurs by Yamada Katsuhisa
Folded from a square of scrapbooking paper