1. Injectivity and essential extensions in equational classes of algebras;Banaschewski,1970
2. Injective sheaves of abelian groups: a counterexample;Banaschewski;Canad. J. Math.,1980
3. When are divisible abelian groups injective;Banaschewski,1979
4. The injective envelope of S-sets;Berthiaume;Can. Math. Bull.,1967