[Advaita-l] Need some help

[kuntimaddi sadananda]

PraNAms:
During the discussions on facebook a seeker asked in response to the discussion on tat tvam asi or brahmaarpanam  where we use bhaga tyaaga lakshana or jaha-ajahallakshana to discard the contradictory attributes and only equate the essence.
Is there a reference to bhaga tyaaga lakshana in Shankara bhashyaas? I appreciate if someone can point to the reference(s). 
Hari Om!Sada

------------------- can you provide citation where Sankara speaks of jahAjahaH lasksana or bahaagatyaaga lakshana. I believe you will only find reference in later sub-commentators who advocate Tat twam asi as a positive pointer. Sankara only refers to it in terms of neti neti in Chandogya and anvaya vyatireka in Upadesa Sahasri. In fact, Sankara advises against lakshana in US18.184