Hadith.4494 - Muhammad ibn Muslim asked Abu Jafar Imam Muhammad ibn Ali Al-Baqir (as) about withdrawal (coitus interruptus).
Imam (as) said: "The semen belongs to the man; he may direct it wherever he wishes."
Al-Kāfi #1913“This is concerning my question before abu ‘Abd Allah (a.s.), about withdrawing before semen discharge. He (the Imam) said, ‘It is up to the...