Brihat Parashara Hora Shastra
पुत्रारिमदगाः सौम्याः स्वभोच्चसुहृदंशगाः । त्रिलाभोदयगाः पापाः कूर्मयोगः स्वभोच्चगाः ॥ २३॥
Kurm Yog. If Putr, Ari and Yuvati Bhava are occupied by benefic Grahas identical with own Bhava, or exaltation, or friendly Rāśi, while malefics are in Sahaj, Labh and Tanu Bhava, in own Bhava, or in exaltation, Kurm Yog is formed.
english translation
putrArimadagAH saumyAH svabhoccasuhRdaMzagAH । trilAbhodayagAH pApAH kUrmayogaH svabhoccagAH ॥ 23॥
hk transliteration by Sanscript