widow

A man married a woman and died before consummating the marriage. Does she still have to observe the `iddah (waiting period)?

Dear scholars, As-Salamu `alaykum. My relative has recently passed away. My question is this: What is his widow supposed to do? We have been told that for four months and ten days, she must wear white clothing and also that she must not put any oil in her hair. Is this an obligation under Islamic law? Jazakum Allah khayran.