Raunkiær, Barclay. “Gervais Lyons: Afghanistan: The Buffer State. Great Britain and Russia in Central Asia. (8VO. VII + 282 Sider + Index. 2 Kort. — Madras:Higginbotham&Co. 1910 London : Luzac & Co”. Geografisk Tidsskrift, bd. 22, januar 1914, https://tidsskrift.dk/geografisktidsskrift/article/view/46839.