Misprints in the book
The Theory of 2Structures
by A. Ehrenfeuct, T. Harju and G. Rozenberg
Updated September 10, 2001
The authors are indept to H. Tverberg, and H. Müller
for pointing out misprints and errors in the book.

Page 23: The definition of degree should read
d_{G}(x) =  { e in E_{G}  e = (x,y) for some y}
This corresponds to the usual definition of degree in graph theory.

Page 34 (line 10): The reference should be
Corneil, Lerchs and Stewart Burlingham (1981)

Page 190: Section 12.2.2 should be moved to Section 13.3.5.
The results of this section concern undirected graphs only.

Page 274: The 15th entry should be
Corneil, D.G., Lerchs, H., and Stewart Burlingham, L. (1981).
Complement reducible graphs. ...