Mahabharata 5.152.11

धुर्ययोर्हययोरेकस्तथान्यौ पार्ष्णिसारथीतौ चापि रथिनां श्रेष्ठौ रथी च हयवित्तथा

dhuryayorhayayorekastathānyau pārṣṇisārathītau cāpi rathināṃ śreṣṭhau rathī ca hayavittathā

Our plain-language meaning of this verse is waiting for scholar review.