Manusmriti
वर्णापेतमविज्ञातं नरं कलुषयोनिजम् । आर्यरूपमिवानार्यं कर्मभिः स्वैर्विभावयेत् ॥ ५७ ॥
A man of impure origin, who belongs not to any caste, (varna, but whose character is) not known, who, (though) not an Aryan, has the appearance of an Aryan, one may discover by his acts.
english translation
varNApetamavijJAtaM naraM kaluSayonijam । AryarUpamivAnAryaM karmabhiH svairvibhAvayet ॥ 57 ॥
hk transliteration by Sanscript