1. P. Lechtken, I. Buethe and A. Hesse (BASF AG), Ger. Patent 2830927, 1980.
2. P. Lechtken, I. Buethe, M. Jacobi and W. Trimborn (BASF AG), Ger. Patent 2909994, 1980.
3. H.-G. Heine, H.J. Rosenkranz and H. Rudolph (Bayer AG), Ger. Patent 3023486, 1980.
4. On the photolysis of acylphosphine oxides: 1. Laser flash photolysis studies with 2,4,6-trimethylbenzoyldiphenylphosphine oxide