Good Manners and Form (Al-Adab)
Bukhari :: Book 8 :: Volume 73 :: Hadith 206
Narrated Jabi:
A man among us begot a boy whom he named Al-Qasim. The people said, "We will not call him (i.e., the father) by that Kuniya (Abu-l-Qasim) till we ask the Prophet about it. The Prophet said. "Name yourselves by my name, but do not call (yourselves) by my Kuniya."