Add an 's to the end of his last name. Ie: Robert Frost's poetry is incredible.
The possessive form is Amos's.
Quantum is singular, not singular possessive. The singular possessive form is quantum's.
The singular form is goose; the singular possessive form is goose's.The plural form is geese; the plural possessive form is geese's.
The singular possessive form is week's.
The singular possessive form is frontiersman's.
The singular possessive form is aircraft's.
The singular possessive form is contralto's.
The singular possessive form is speculum's.
The singular possessive form is herd's.
The singular possessive form is heart's; the plural possessive form is hearts'.
The singular form for the noun families is family. The singular possessive form is family's.
The singular possessive form of wolves is wolf's.