Analysis of information sources in references of the Wikipedia article "West Semitic languages" in English language version.
P. Haupt (1878) first recognized that the qatala past tense found in West Semitic was an innovation, and that the Akkadian prefixed past tense must be archaic. It was F. Hommel, however, who recognized the implications of this for the subgrouping of Semitic; cf. Hommel(1883: 63, 442; 1892: 92–97; 1926: 75–82).
P. Haupt (1878) first recognized that the qatala past tense found in West Semitic was an innovation, and that the Akkadian prefixed past tense must be archaic. It was F. Hommel, however, who recognized the implications of this for the subgrouping of Semitic; cf. Hommel(1883: 63, 442; 1892: 92–97; 1926: 75–82).