There have been created many variations of the traditional crane. Cranes have also been used to create modulars, where they are usually connected by inserting a petal fold of the connecting module into the petal fold of the wing.
The model in the picture is an elegant crane modular by Kittaka Mihoko. The instructions are available in the book, Crane Origami, by Tomoko Fuse, ISBN 9784416302057 (in Japanese).
It consists of 6 cranes connected with 4 corner modules. There's an independent tetrahedron locked inside the crane's frame.
The tetrahedron is folded with two 6" (150 mm) squares of scrapbook paper. The cranes and the corner modules must be folded with squares whose sides are 4/5 of the sides of the squares used for the tetrahedron. I folded them with regular origami paper that I cut to size from 6" (150 mm) squares.