Sources for Alexander: Modern and Ancient

From Wikipedia:

The five main surviving accounts are by Arrian, Curtius, Plutarch, Diodorus, and Justin.

• Anabasis Alexandri (The Campaigns of Alexander in Greek) by the Greek historian Arrian of Nicomedia, writing in the 2nd century AD, and based largely on Ptolemy and, to a lesser extent, Aristobulus and Nearchus. It is considered generally the most trustworthy source.
• Historiae Alexandri Magni, a biography of Alexander in ten books, of which the last eight survive, by the Roman historian Quintus Curtius Rufus, written in the 1st century AD, and based largely on Cleitarchus through the mediation of Timagenes, with some material probably from Ptolemy;
• Life of Alexander (see Parallel Lives) and two orations On the Fortune or the Virtue of Alexander the Great (see Moralia), by the Greek historian and biographer Plutarch of Chaeronea in the second century, based largely on Aristobulus and especially Cleitarchus.
• Bibliotheca historia (Library of world history), written in Greek by the Sicilian historian Diodorus Siculus, from which Book 17 relates the conquests of Alexander, based almost entirely on Timagenes's work. The books immediately before and after, on Philip and Alexander's "Successors," throw light on Alexander's reign.
• The Epitome of the Philippic History of Pompeius Trogus by Justin, which contains factual errors and is highly compressed. It is difficult in this case to understand the source, since we only have an epitome, but it is thought that also Pompeius Trogus may have limited himself to use Timagenes for his Latin history.

To these five main sources some scholars add the Metz Epitome, an anonymous late Latin work that narrates Alexander's campaigns from Hyrcania to India. Much is also recounted incidentally in other authors, including Strabo, Athenaeus, Polyaenus, Aelian, and others.

Plutarch offers a list of some of his sources:

46 Here the queen of the Amazons came to see him, as most writers say, among whom are Cleitarchus, Polycleitus, Onesicritus, Antigenes, and Ister; 2 but Aristobulus, Chares the royal usher, Ptolemy, Anticleides, Philo the Theban, and Philip of Theangela, besides Hecataeus of Eretria, Philip the Chalcidian, and Duris of Samos, say that this is a fiction.