In his Introduction in Volume I of his Lectures on the History of Philosophy 1825-1826 (Trans. Robert F. Brown and J.M. Stewart, Clarendon Press, Oxford, 2009), Hegel named nine of his sources (pp. 99-101).
In that order (I use the details from the Bibliography), I exemplify references to Cusanus below the title:
Wilhelm Gottlieb Tennemann, Grundriss der Geschichte der Philosophie für den akademischen Unterricht, 3rd edn., ed. Amadeus Wendt (Leipzig, 1820)
From Contents
Thomas Stanley, Historia philosophiae vitas opiniones resque gestas et dicta philosophorum sectae cuiusuis complexa… (Leipzig, 1711) (Latin translation from English)
Hegel wrote ‘Its dominant viewpoint is that there are only ancient philosophies, and the era of philosophy was cut short by Christianity. So this treatise only contains the ancient schools…’
Jacob Brucker, Historia critica philosophiae, 4 vols. (Leipzig, 1742-4). (Hegel owned the 1756 edn.)
From page 360 of vol. 4.1
Dieterich Tiedemann Geist der spekulativen Philosophie 6 vols. (Marburg, 1791-7). (Hegel owned vols. i-iii)
Page 321 of vol. 5
Dieterich Tiedemann Dialogorum Platonis argumenta, expounded and illustrated 12. vols. (Zweibrücken, 1786)
This text, as its title indicates, is a study of the Platonic dialogues.
Johann Gottlieb Buhle, Lehrbuch der Geschichte der Philosophie und einer kritischen Literatur derselben, 8 pts. in 9 vols. (Göttingen, 1796-1804)
From page 101 of vol. 6.1
Wilhelm Gottlieb Tennemann, Geschichte der Philosophie, 11 vols. (Leipzig, 1798-1819)
Contents of vol. 9
Friedrich Ast, Grundriss der Geschichte der Philosophie (Landshut, 1807)
From page 315
Thaddä Anselm Rixner, Handbuch der Geschichte der Philosophie zum Gebrauche seiner Vorlesungen, 3 vols. (Sulzbach, 1822-3)
Hegel wrote ‘Most worth recommending is Rixner’s Handbuch der Geschichte der Philosophie in 3 volumes (Sulzbach, 1822-3)…he is a man of intelligence who provides a particularly useful selection of key passages…the accuracy of the citations and the other features make it highly commendable.’
From page 164 of vol. 2
Most importantly, Hegel did not name the other history by Buhle that he used – Geschichte der neuern Philosophie seit der Epoche der Wiederherstellung der Wissenschaften, 6 vols. (Göttingen, 1800-4). Brown, the editor, showed in his Notes that Hegel paid close attention to it with regard to his writing on Bruno (see vol. III, The Second Period: Medieval Philosophy, Notes 102, 104, 126, 129).
The most thorough discussion of Cusanus’ philosophy in comparison to Hegel’s sources above is in volume 2.1 of this history by Buhle, between pp. 341-353 (the Notes refer to both 2.1 and 2.2).
From page 342 of vol. 2.1
Cusanus’ texts referred to in volume 2 of Buhle’s History
De concordantia catholica (On Catholic Concordance, 1434)
De docta ignorantia (On Learned Ignorance, 1440 – Buhle discusses)
De coniecturis (On Surmises, 1441-2 – Buhle discusses)
De Ignota Litteratura (On Unknown Learning, 1442-3 – Johannes Wenck)
De quaerendo Deum (On Seeking God, 1445)
De dato patris luminum (On the Gift of the Father of Lights, 1446)
Apologia doctae ignorantiae discipuli ad discipulum (A Defence of Learned Ignorance from One Disciple to Another, 1449)
(Idiota) de sapientia (The Layman of Wisdom, 1450 – Buhle discusses)
Epistolae contra Bohemos (Epistles Against the Bohemians/Hussites, 1452)
De visione Dei (On the Vision of God, 1453)
De mathematica perfectione (On Mathematical Perfection, 1458)
Cribrationes Alchorani (Cribratio Alkorani, A Scrutiny of the Koran, 1461)
De venatione sapientiae (On the Pursuit of Wisdom, 1463)
De apice theoriae (On the Summit of Contemplation, 1464 – Cusanus’ last work)
From the Index, vol. 6
‘Hegel the consummate Neoplatonist’ A
‘Hegel the consummate Neoplatonist’ B
materialism, mysticism and art 