[156] Ibid: 409-410.
[157] The Tychonic system has supporters to this day. See [chap. v].
[158] Dreyer: 181.
[159] The authoritative biography is the Vita by Frisch in vol. VIII, pp. 668-1028 of Op. Om. Kep.
[160] Frisch: VIII, 718.
[161] Delambre: Astr. Mod. 314-315.
[162] Frisch: VIII, 999.
[163] Ibid: VIII, 696.
[164] Ibid: VIII, 699-715.
[165] Dreyer: 290-309.