TDS on Contract

I have a small query, In regard to sec 194c towards tds on contracts, it is unclear on the nature of the contract whether the contract should be duly signed by the parties and on paper (in writing) or whether an implied or a verbal contract (or sometimes not even a contract i.e., say u pay a newspaper towards advertising  a certain sum every month without entering into a contract), will they deem to be a contract and shoul tds be deducted on the amount payable??