1. Poggendorff's. Annalen Vol. xcix, 315–315. This was first printed separately by A. W. Hayn in Berlin, and after-wards appeared in
2. Poggendorff's. Annalen Vol. lxxix, 393–393. Phil. Mag. vol. ii. pp. 1, 102
3. Poggendorff's. Annalen Vol. lxxix, 394–394. Phil. Mag. vol. ii. p. 1