source Journal of the Society of Motion Picture Engineers January 1938 p96
Vieth 氏と Wiebusch 氏の縦溝記録装置の論文のアブストラクト
Abstract section of Vieth Wiebuschs hill and dale recorder paper
“Recent Development in Hill and Dale Recorders” (Vieth and Wiebusch, JSPTE, 1938)