D. B. Butler
- The Finer Grinding of Portland Cement, and the Comparative Value of the Coarser Particles. Dans: Minutes of the Proceedings of the Institution of Civil Engineers, v. 132, n. 1898-2 ( 1898). (1898):
- The Specific Gravity of Portland Cement. Dans: Minutes of the Proceedings of the Institution of Civil Engineers, v. 166, n. 1906-4 ( 1906). (1906):