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平台:
Emerald Backfiles
(Available from 1972 volume: 1 issue: 1 until 1993 volume: 22 issue: 8.)
Emerald Journal
(Available from 2002 until 2014. Available from 2007 until 2018.)
ProQuest SciTech Premium Collection
(Available from 1995/01/01. Most recent 1 year(s) not available.)