Lithops subg. Xantholithops Schwantesin Natl. Cact. Succ. J. 6: 23. 1951, nom. illeg., sec. Cole & Cole 20172,1
1.Cole, D. T. & Cole, N. A. 2017: Lithops. – In: Hartmann, H. E. K., Illustrated handbook of succulent plants. Aizoaceae, ed. 2. – Berlin: Springer, 2.Cole, D. T. & Cole, N. A. 2017: Lithops. – In: Hartmann, H. E. K., Illustrated handbook of succulent plants. Aizoaceae, ed. 2. – Berlin: Springer