Haapala, P. (1936). On serpentine rocks in northern Karelia: With 21 figures in text and two maps. Government Press.
Lua i Stíl Chicago (17ú heag.)Haapala, Paavo. On Serpentine Rocks in Northern Karelia: With 21 Figures in Text and Two Maps. Helsinki: Government Press, 1936.
Lua MLA (8ú heag.)Haapala, Paavo. On Serpentine Rocks in Northern Karelia: With 21 Figures in Text and Two Maps. Government Press, 1936.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.