Citazione Stile APA (7a Edizione)

Lenchner, G., & Krulik, S. (1974). The overhead projector in the mathematics classroom. National Council of Teachers of Mathematics.

Citazione stile Chigago Style (17a edizione)

Lenchner, George, e Stephen Krulik. The Overhead Projector in the Mathematics Classroom. Reston, VA: National Council of Teachers of Mathematics, 1974.

Citatione MLA (9a ed.)

Lenchner, George, e Stephen Krulik. The Overhead Projector in the Mathematics Classroom. National Council of Teachers of Mathematics, 1974.