vṛtraḥ

Vṛtra — SB 6.9.18, SB 6.17.38

Vṛtrāsura — SB 6.12.4, SB 6.12.6, SB 6.12.24, SB 6.14.6, SB 8.11.35, SB 10.6.13

Vṛtrāsura, the commander of the demons — SB 6.10.30

the great hero Vṛtrāsura said — SB 6.11.14