Sa'd bin Hisham bin 'Amir سعد بن هشام بن عامر · The Book of Marriage

It was narrated from 'Alqamah, that 'Uthman said to Ibn Mas'ud: "Shall I arrange for you to marry a young girl?" 'Abdullah called 'Alqamah and he told the people that the Prophet said: "Whoever among you can afford it, let him get married, for it is more effective in lowering the gaze and guarding chastity. And whoever cannot afford it, then let him fast, for it will be a restraint for him."

It was narrated that 'Abdullah said: "The Messenger of Allah said to us: 'O young men, whoever among you can afford it, let him get married,'" and he quoted the same hadith.