Can anyone point me to any useful secondary literature on the use of the defective verb aaha with past sense (contravening Paa.nini 3.4.84+anuv.rtti)? Does anyone happen to know when the awkwardness of this usage was first explained away by declaring aaha to be `[kaalasaamaanyavaacakas] ti"nantapratiruupako nipaata.h'? Dominic Goodall