Robert Singh. American Government and Politics: A Concise Introduction. SAGE.
Citazione stile Chigago Style (17a edizione)Robert Singh. American Government and Politics: A Concise Introduction. SAGE.
Citatione MLA (8a ed.)Robert Singh. American Government and Politics: A Concise Introduction. SAGE.
Attenzione: Queste citazioni potrebbero non essere precise al 100%.