Indian Contract Act, 1872
231. Right of parties to a contract made by agent not disclosed
If an agent makes a contract with a person who neither, knows nor has reason to suspect, that he is an agent, his principal may require the performance of the contract; but the other contracting party has, as against the principal, the same right as he would have had as against if the agent had been the principal.
If the principal discloses himself before the contract is completed, the other contracting party may refuse to fulfill the contract, if he can show that, if he had known who was the principal in the contract, or if he had known that the agent was not a principal, he would not have entered into the contract.