Transmitter identification depends on several types of reference works. Collections of ṭabaqāt clarify generations and teacher–pupil links, while historical compilations record periods and biographical events.
Examples include Ibn Saʿd’s al-Ṭabaqāt, al-Bukhārī’s historical works, the history of Ibn Abī Khaythama, and Ibn Abī Ḥātim’s al-Jarḥ wa-al-Taʿdīl. These provide complementary evidence rather than identical coverage.
Because a source may abbreviate names or omit a particular detail, difficult identifications often require comparison across independent reference works.