Citazione APA

Gladden, W. (1904). Where does the sky begin? Houghton, Mifflin and company.

Stile di citazione Chicago

Gladden, Washington. Where Does the Sky Begin? Boston and New York: Houghton, Mifflin and company, 1904.

Citazione MLA

Gladden, Washington. Where Does the Sky Begin? Houghton, Mifflin and company, 1904.