Part,  -

1   7 1 | 20 R V.78.- 79 {1/21} <V>asuṅi upadeśivadvacanam svarasiddhyartham
2   7 1 |    20 R V.78.- 79 {2/21} asuṅi upadeśivadbhāvaḥ vaktavyaḥ .~(
3   7 1 |   6/21} upadeśāvasthāyām asuṅi kṛte iṣṭaḥ svaraḥ yathā
4   7 1 | 21} tasmāt suṣṭhu ucyate asuṅi upadeśivadvacanam svarasiddhyartham