Declension table of ?mānasya

Masculine	Singular	Dual	Plural
Nominative	mānasyaḥ	mānasyau	mānasyāḥ
Vocative	mānasya	mānasyau	mānasyāḥ
Accusative	mānasyam	mānasyau	mānasyān
Instrumental	mānasyena	mānasyābhyām	mānasyaiḥ mānasyebhiḥ
Dative	mānasyāya	mānasyābhyām	mānasyebhyaḥ
Ablative	mānasyāt	mānasyābhyām	mānasyebhyaḥ
Genitive	mānasyasya	mānasyayoḥ	mānasyānām
Locative	mānasye	mānasyayoḥ	mānasyeṣu

Compound mānasya -

Adverb -mānasyam -mānasyāt