1. Homotopy with respect to a ring;Bousfield, A. K.,1971
2. 2. J. Kettner, Thesis, M. I. T., Cambridge, Mass., 1972.
3. On a theorem of Borsuk;Moore, J. C.;Fund. Math.,1956
4. Steenrod operations in the Eilenberg-Moore spectral sequence;Rector, David L.;Comment. Math. Helv.,1970