1. According to the Nakazaki's article,1 the sketch in Figure 1 originates from Kekulé's Lehrbuch der Organischen Chemie, Vol. II as pointed out by Lowry: T. M. Lowry, Optical Rotatory Power, Longman, Green & Co., London, 1935.
2. The sketch in Figure 2 was taken from the Pasteur's original paper: L. Pasteur, Ann. Chim. Phys., 1850, 28 (3), 56. However, at the same time, Pasteur pointed out that the actual form of the crystals was more complex than that shown in Figure 2.
3. The resolution of racemic acid: A classic stereochemical experiment for the undergraduate laboratory