【E-book】ProQuest Ebook Central Maintenance Alert（6/26 23:00 - 6/27 7:00）

ProQuest Ebook Central may not be available during the following period due to system maintenance.
Sorry for inconvenience.

【Maintenance Period (JST)】 From 26 (Sat) 23:00 to 27 (Sun) 7:00 June, 2021