APA

National Endowment for the Humanities, National Endowment for the Humanities, . (1991). Challenge grants: guidelines, application instructions and administrative requirements. Washington: The Endowment.

Chicago

National Endowment for the Humanities, National Endowment for the Humanities, . 1991. Challenge grants: guidelines, application instructions and administrative requirements. Washington: The Endowment.

Harvard

National Endowment for the Humanities, National Endowment for the Humanities, . (1991). Challenge grants: guidelines, application instructions and administrative requirements. Washington: The Endowment.

MLA

National Endowment for the Humanities, National Endowment for the Humanities, . Challenge grants: guidelines, application instructions and administrative requirements. Washington: The Endowment. 1991.