R. E. Fairbairn, S. J. Teat, K. J. Gagnon, and S. J. Dalgarno, “A Convenient Synthetic Route to Partial-Cone p-Carboxylatocalix[4]arenes”, Chimia, vol. 69, no. 9, p. 516, Sep. 2015, doi: 10.2533/chimia.2015.516.