The Altindische Grammatik is the monumental Sanskrit grammar by Jacob Wackernagel (1853–1938), after his death continued by Albert Debrunner, published in Göttingen between 1896 and 1957.
The work presents a full discussion of Sanskrit phonology and nominal morphology, but a treatment of the verb is lacking.
A fourth volume covering the verb was in preparation by Karl Hoffmann, but was never published, and to this day (the 2010s), a thorough discussion of the Sanskrit verbal system is lacking.
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