The alternation of avalokitasvara and avalokitezvara in all
likelihood points to some underlying Prakrit where svara and -zvara would
both be reduced to -(s)sara, cf. the usage of Pali where Skt. svara is
represented by sara, and Skt. iizvara by issara. Sanskritization of
originally Prakrit words creates multiple possibilities in Sanskrit.
Madhav Deshpande