提示：此条目页的主题不是
曲尺。
角尺，也称为直角尺、折尺（英语：Steel square），是一种金属制作的直角尺。这个工具的主要用途测量精度直角（90度）的表面。有些角尺上标示公制或英制刻度以方便测量。
一个有刻度直角尺
- 《机械测量入门》，安改娣,格日勒，化学工业出版社，ISBN：9787122009180 / 7122009181
- Siegele, H.H. The Steel Square. Sterling Publishing. 1981. ISBN 0-8069-8854-1.
- Ulrey, Harry F. Carpenters and Builders Library No.3. Theodore Audel. 1972. LCCN 74099760.
- Schuttner, Scott. Basic Stairbuilding,. Taunton Press. 1990. ISBN 0-942391-44-6.
- Spence, William P. Constructing Staircases Balustrades & Landings. Sterling Publishing. 2000. ISBN 0-8069-8101-6.
- Gochnour, Chris. 11 Essential Measuring and Woodworking Tools. Fine Woodworking (Taunton Press). February 2006, (182): 75.
- Lanham, Wm. The Steel Square. Bath: E. A. Lovell.
- Falconer, John. Ednie, John (editor) , 编. The Steel Square. Carpentry and Joinery Vol. V. Gresham. 1925.
- Sobon, Jack. Build a classic timber-framed house : planning and design, traditional materials, affordable methods. Pownal, Vt. : Storey Communications. 1994. ISBN 0882668420.
