User contributions
- 12:15, 27 April 2015 (diff | hist) . . (+5) . . 1517: Spectroscopy (→Explanation)
- 12:13, 27 April 2015 (diff | hist) . . (+190) . . 1517: Spectroscopy (→Explanation)
- 11:53, 27 April 2015 (diff | hist) . . (+1,118) . . 1517 (→Explanation)