## Homology, Homotopy and Applications

Homology, Homotopy and Applications (HHA) is a fully refereed international journal dealing with homology and homotopy in algebra and topology and their applications to the mathematical sciences.

Category of $A_\infty$-categoriesVolume 5, Number 1 ( 2003 )
Extensions of semimodules and the Takahashi functor $\rm Ext_\Lambda(C,A)$.Volume 5, Number 1 ( 2003 )