|
| To develop strong ties | Drnovsek et al., 2008 [80] ; Presutti et al., 2011 | |
| · Contractual relationships and enforcement are unnecessary | Drnovsek et al., 2008 | ||
| · Intensity of cooperation | |||
| · Direct and close relationship | Drnovsek et al., 2008; Van Gelderen, 2010; Ren et al., 2014 [81] Sigfusson and Harris, 2012 | ||
| · Frequency of a relationship | Howorth and Moro, 2006 [13] ; Van Gelderen, 2010; Ren et al., 2014 | ||