“…Research Development [6], [10], [13], [14], [15], [16], [18], [19] Being tested with larger sample [4], [20], [21] Being tested in different countries [4], [17] The relationship between customers and sellers [22], [23] Qualitative assessment [24], [21] Being tested with different case study [25], [19] The test on customer's perspective [26] Research opportunity is organized based on numbers of supporting literatures. There are six literatures which support research development, both for research model and technology aspect.…”