1. Varieties of Groups
2. [5] Kovács L.G. and Newman M.F. , “On non-Cross varieties of groups”, J. Austral. Math. Soc. (to appear).
3. On critical groups
4. Endliche Gruppen I
5. [2] Gaschütz Wolfgang , Selected topics in the theory of soluble groups (Lectures given at the Ninth Summer Research Institute of the Australian Mathematical Society in Canberra, 1969. Notes by J. Looker).