SCHACH von WITTENAU, M. and BLACKWOOD, Robert K. Proton Magnetic Resonance Spectra of Tetracyclines. Journal of Organic Chemistry (J. Org. Chem.). 1966, vol. 31, iss. 2, s. 613–615. Publ. date (print): February 1, 1966. https://doi.org/10.1021/jo01340a519
MUXFELDT, Hans and ROGALSKI, Werner. Tetracyclines. A Total Synthesis of (±)-6-Deoxy-6-demethyltetracycline. Journal of the American Chemical Society (J. Am. Chem. Soc.). 1965, vol. 87, iss. 4, s. 933–934. Publ. date (print) February 1, 1965. https://doi.org/10.1021/ja01082a056