International Tunnelling Association. (1986). Tunnelling and Underground Space Technology. Pergamon Press.
Citação do estilo Chicago (17ª ed.)International Tunnelling Association. Tunnelling and Underground Space Technology. Oxford, Inglaterra: Pergamon Press, 1986.
Citação MLA (8ª ed.)International Tunnelling Association. Tunnelling and Underground Space Technology. Pergamon Press, 1986.
Rhybudd: Mae'n bosib nad yw'r dyfyniadau hyn bob amser yn 100% cywir.