“…First, it marks a time of substantial change and "a period of great intellectual ferment in the discipline" (De Maio and Kushner 1981, 183). Finally, an end point at or near mid-century is a popular one for researchers (see, for example, De Maio and Kushner 1981;Hudson 1996;Miller, Tien, and Peebler 1996a). Finally, an end point at or near mid-century is a popular one for researchers (see, for example, De Maio and Kushner 1981;Hudson 1996;Miller, Tien, and Peebler 1996a).…”