توثيق جمعية علم النفس الأمريكية APA (الطبعة السابعة)

Sahlén, K. (1992). Anatomical and physiological ripening of Pinus sylvestris L. seeds in northern Fennoscandia. Dept. of Silviculture, Swedish University of Agricultural Sciences.

توثيق أسلوب شيكاغو (الطبعة السابعة عشر)

Sahlén, Kenneth. Anatomical and Physiological Ripening of Pinus Sylvestris L. Seeds in Northern Fennoscandia. Umeå, Sweden: Dept. of Silviculture, Swedish University of Agricultural Sciences, 1992.

توثيق جمعية اللغة المعاصرة MLA (الطبعة الثامنة)

Sahlén, Kenneth. Anatomical and Physiological Ripening of Pinus Sylvestris L. Seeds in Northern Fennoscandia. Dept. of Silviculture, Swedish University of Agricultural Sciences, 1992.