Whose idea was it to change the graduation ceremony music A: The speaker's. B: Edwin Elgar's. C: The committee's. D: The students'.

请问,以下这篇文献属于哪种文献类型?Karlsson C (2011) Clusters, networks, and creativity. In: Andersson D, Andersson A, Mellander C (eds) Handbook of creative cities. Edward Elgar, Northampton, MA.