In R̥gveda 10.127.3 there is a verb form askr̥ta showing the trace of the root skr̥.  The Padapāṭha of Śākalya presents this form as akr̥ta, indicating that the root skr̥ as an independent root is no longer recognized. What is going on? Can one presume that forms like saṃskaroti where Pāṇini prescribes the insertion of "s" are actually survivals of this earlier root skr̥.  Please suggest references that I can look up.