Garudapurana 1.65.36

1.65.36

aromaśā bhugnapṛṣṭhaṃ śubhaṃ cāśubhamanyathā /
kakṣāśvatthadalā śreṣṭhā sugandhirmṛgaromikā //

A hairless and bowed back is auspicious, and otherwise inauspicious. / An armpit shaped like an aśvattha leaf, fragrant, and with deer-like hair is best;