Held that from books of account and corroborative documents placed on record, it was found that there was no dispute about availability of cash balance and its source as assessee duly recorded it in its books of account. Once, availability of cash in hand was proved, assessee could not be asked to furnish proof of acquisition of such amount in currency notes of particular denomination.  Cash balance being part of sale of medicines and hospital receipts, could not be brought to tax at hands of assessee again which will otherwise lead to taxing same amount twice. Addition is deleted. Held addition made an upward estimation and directed Assessing Officer to increase declared book profit by 4 per cent of total amount deposited by assessee in Specified Bank Notes  is deleted.   (AY. 2017-18)