Brahma Sutras
ॐ क्षत्रियत्वागतेश्चोत्तरत्र चैत्ररथेन लिङ्गात् ॐ ॥ १-३-३५॥
And because his Kshatriyahood is known later on from the indicatory mark of his mention along with a descendant of Citraratha.
english translation
OM kSatriyatvAgatezcottaratra caitrarathena liGgAt OM ॥ 1-3-35॥
hk transliteration by Sanscript