@misc{1191851, author = {C E Waters}, title = {Circular of the Bureau of Standards no. 431::typewriter ribbons and carbon paper}, year = {1941}, month = {1941-01-01 05:01:00}, publisher = {, National Institute of Standards and Technology, Gaithersburg, MD}, doi = {https://doi.org/10.6028/NBS.CIRC.431}, language = {en}, }