Musnad Ahmad 656:6

Yazid narrated to us, Sufyan informed us, from Mansur, from Ibrahim, from Alqama, who said: Abdullah was approached regarding a woman whom a man married, then he died, and he had not specified a dowry for her, nor had he consummated the marriage with her. He said: They differed before him, so he said: "I see that she is entitled to a dowry like that of her peers, she has the right of inheritance, and she must observe the waiting period (iddah)." Ma'qil ibn Sinan al-Ashja'i then testified that the Messenger of Allah (peace and blessings of Allah be upon him) had judged in the case of Birwa' bint Washiq with the same as this.