“…Incumbent companies were asked to indicate on a five-point Likert scale to what extent new competitors would encounter the barrier in Structural Access to distribution/selling expenses (13) Porter (1980), Yip (1982), Karakaya and Stahl (1989), Han et al (2001) Access to knowledge/skilled labour/patents/ technological change (3) Yip (1982), Harrigan (1983), Karakaya and Stahl (1989), Shepherd (1997) Advertising (14) Spence (1980), Harrigan (1981), Yip (1982), Netter (1983), Schmalensee (1983), Karakaya and Stahl (1989) Capital requirements (22) Bain (1956), Porter (1980), Harrigan (1981), Yip (1982), Karakaya and Stahl (1989), Shepherd (1997) Sales volume (23) Yip (1982) Cost disadvantages or experience disadvantages of newcomers (19) Bain (1956), Scherer (1970), Yip (1982), Karakaya and Stahl (1989), Geroski et al (1990), Han et al (2001) Costs of capital/special risks and uncertainties (18) Demsetz (1982), Shepherd (1997) Customer switching costs (7) Porter (1980), Klemperer (1987Klemperer ( , 1992, Karakaya and Stahl (1989), Shepherd (1997), Shy (2002) Differentiation (16) Bain …”