The quest is listed as heroic but can be soloed. Quests from Virlana Levora and The Maladjusted Codex will need to be done before he will speak with you. Also: be sure you have read the in-game mail from Justinian Theo and examined the square coin that came with the mail. It is possible to do all the library quests without having read the mail or examined the coin, but then you will get to the signature line and won't be able to receive the quest from Maelin or see the book in the South Wing Stacks.
Note: being in a raid or group can hide the sparkly locations that are needed during the quest. if that happens leave raid/group and zone-in/out and sparklies will be shown again.