Starting in the 1960s with simple linear ‘‘technology push’’ (e.g. Carter and Williams, 1957), and ‘‘need pull’’ models in the 1970s (e.g. Myers and Marquis, 1969), through the ‘‘coupling model’’ of the late 1970s (Rothwell, 1974; Mowery and Rosenberg, 1978) to early 1980s to the
integrated model of Rothwell (1992)