APA Citatie

Giles, F., Keith, R. M., & Saupe, D. C. Herbaceous perennials. Reston publishing company.

Chicago Style citaat

Giles, F.A, Rebecca Melntosh Keith, en Donald C. Saupe. Herbaceous Perennials. Reston: Reston publishing company.

MLA citatie

Giles, F.A, et al. Herbaceous Perennials. Reston publishing company.