Gaya APA

Checkland, P. (1999). Soft systems methodology: a 30-year retrospective (-). (4) Organisasi Perusahaan: Teo: Makmur Tanjung Lestari.

Gaya MLA

Checkland, P.. Soft systems methodology: a 30-year retrospective. - (4) Organisasi Perusahaan: Teo: Makmur Tanjung Lestari, 1999. Text.