Musannaf Ibn Abi Shayba 9:482

Yazid ibn Harun narrated to us, he said: Yahya ibn Sa'id informed us, from Muhammad ibn Ibrahim al-Taymi, that Abu Hadrad al-Aslami sought the help of the Messenger of Allah (may Allah bless him and grant him peace) regarding the dowry of a woman he had married. The Messenger of Allah (may Allah bless him and grant him peace) asked him, "How much did you settle as a dowry for her?" He said, "Two hundred dirhams." The Messenger of Allah (may Allah bless him and grant him peace) said, "If you were scooping from Buthan, you would not have added more."