Shiva Purana

siva.sh/siva-purana/saturda-samhita/5/44

तदा षष्ठेन चांशेन कृष्णः पुरुषसत्तमः ।। वसुदेवसुतः श्रेष्ठो वासुदेवो भविष्यति।। ४४।।

sanskrit

Then, with the sixth part, Krishna, the Supreme Personality of Godhead, appeared. The best son of Vasudeva will be Vasudeva.

english translation

tadA SaSThena cAMzena kRSNaH puruSasattamaH || vasudevasutaH zreSTho vAsudevo bhaviSyati|| 44||

hk transliteration by Sanscript