Source: Spain National Library: http://bdh-rd.bne.es/viewer.vm?id=0000092068&page=1
Modulation key
Author: Antonio Soler (1729-1783) Edition: Madrid: Ibarra, 1762.
Teaching Topic Theory
Source: Spain National Library: http://bdh-rd.bne.es/viewer.vm?id=0000092068&page=1