Spencer, Herbert, 1820-1903 ; Panīpatī, K̲h̲vājah G̲h̲ulāmulḥasnain (1904) Falsafah-yi taʻlīm : yaʻnī, Ḥakīm Harbaṭ Ispinsar kī kitāb "Ejūkeshan" kā tarjamah. Anjuman Taraqqī-yi Urdū. ISBN: .