Touillaux, R., Tinant, B., Van Meerssche, M., Dereppe, J.-M., Leroy, G., & Weiler, J. (1981). Configuration and C-13 Nmr-spectra of 1-pyrazolines. Organic Magnetic Resonance, 16(1), 73-74. https://doi.org/10.1002/mrc.1270160121 (Original work published 1981)