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"O young people! Whoever among you can support a wife should marry, for that is more modest for the gaze and safer for your private parts." [Bukhari and Muslim]
I cannot give the reference but I have heard this Hadeeth. Prophet (peace and blessing of Allah be upon him said) " O young people, get married as soon as possible..... ". The ..... means that something followed and I don't remember it.
I think its the one posted by brother AabiruSabeel and even that has a little more to it:
“O Young people! Whoever among you is able to marry, should marry, because it helps him lower his gaze and guard his modesty, and whoever is not able to marry, should fast, as fasting will diminish his sexual power"