Archelon by Fumiaki Kawahata

Diagrams in Dinosaurs and Paleontology in Origami by Fumiaki Kawahata
Diagrams in Origami Dinosaurs 3 by Fumiaki Kawahata
Folded from a square of Vietnamese wrapping-paper

Elasmosaurus by John Montroll

Diagrams in Dinosaur Origami by John Montroll
Folded from a square of tie-dyed paper

Quetzalcoatlus by John Montroll

Diagrams in Dinosaur Origami by John Montroll
Folded from a square of textured origami paper