Aṣṭāṅgahṛdayasaṃhitā

aśvapṛṣṭhagamanaṃ calarodhaṃ madyamaithunamajīrṇamasātmyam||44||
sāhasāni vividhāni ca rūḍhe vatsaraṃ pariharedadhikaṃ vā||44||
ṣṭāviṃśo+adhyāyaḥ||28||