From these countless hundreds of mantras of the Yajur Veda, the powerful sage compiled fifteen new branches of Vedic literature. These became known as the Vājasaneyi-saṁhitā because they were produced from the hairs of the horse’s mane, and they were accepted in disciplic succession by the followers of Kāṇva, Mādhyandina and other ṛṣis.
Srimad Bhagavata Purana
श्रीमद्भागवतमहापुराणम्
मूल श्लोकः
यजुर्भिरकरोच्छाखा दशपञ्च शतैर्विभुः । जगृहुर्वाजसन्यस्ताः काण्वमाध्यन्दिनादयः
yajurbhirakarocchākhā daśapañca śatairvibhuḥ | jagṛhurvājasanyastāḥ kāṇvamādhyandinādayaḥ
SB 12.6.74