Gel’mbol’dt, V. O., Filinchuk, Y., & Koroeva, L. V. (2003). Crystal structure of N,N′-di-tert-butylurea as a N,O-donating ligand. Russian Journal of Coordination Chemistry, 29(11), 818. https://doi.org/10.1023/B:RUCO.0000003440.74464.4a (Original work published 2003)