Brihat Parashara Hora Shastra
आरूधात् सप्तमे केतुः पापखेटयुतेक्षितः । साहसी श्वेतकेशी च वृद्धलिङ्गी भवेन्नरः ॥ २४॥
Should there be Ketu in the 7th from Lagn Pad, receiving a Drishti from, or being yuti with another malefic, the native will be adventurous, will have (prematurely) grey hair and a big male organ.
english translation
ArUdhAt saptame ketuH pApakheTayutekSitaH । sAhasI zvetakezI ca vRddhaliGgI bhavennaraH ॥ 24॥
hk transliteration by Sanscript