Manusmriti
कामतो रेतसः सेकं व्रतस्थस्य द्विजन्मनः । अतिक्रमं व्रतस्याहुर्धर्मज्ञा ब्रह्मवादिनः ॥ १२० ॥
Those who know the Veda declare that a voluntary effusion of semen by a twice-born (youth) who fulfils the vow (of studentship constitutes) a breach of that vow.
english translation
kAmato retasaH sekaM vratasthasya dvijanmanaH । atikramaM vratasyAhurdharmajJA brahmavAdinaH ॥ 120 ॥
hk transliteration by Sanscript