1. On the structure and applications of the Steenrod algebra;Adams;Comment. Math. Helv.,1958
2. Algebraic Homotopy;Baues,1989
3. The Algebra of Secondary Cohomology Operations;Baues,2006
4. Higher order track categories and the algebra of higher order cohomology operations;Baues;Georgian Math. J.,2010
5. Comparing cohomology obstructions;Baues;J. Pure Appl. Algebra,2011