Annick Therrien was a Technical Animator who worked on Ghostbusters.
Annick Therrien was an effects animator on "Star Wars VI - The Return of the Jedi," and supervised on "Poltergeist II," "Big Trouble in Little China," "Alien 3," and "Batman Returns."
Annick Therrein and the technical animation team fixed the Library ghost's book so that it looked like an actual object rather than looking ghostly, too. The book was rotoscoped and treated accordingly.  According to Richard Edlund, Therrein kept the team in check during production.  Therrein recounted it would take three weeks to produce one to two seconds of animation. She would print an image down and on a cell would use a repeatograph at #0-0-0-5-0, outline frame by frame for each character, paint in black and shoot in bottom light. 
- Richard Edlund (1999). Ghostbusters (1984) "SFX Team Featurette" (1999) (DVD ts. 05:02-05:12). Columbia Pictures. Richard Edlund says: "And her book, I remember. She was kinda soft and diffused. But her book had to be sharp which we had Annick's people fix so the book was rotoscoped so it was separately treated."
- Richard Edlund (1999). Ghostbusters (1984) "SFX Team Featurette" (1999) (DVD ts. 05:26-05:37). Columbia Pictures. Richard Edlund says: "Annick was also... she took the bull by the horns and uh if somebody wasn't producing, she'd let'em know. And it was very effective, I think."
- Annick Therrien (1999). Ghostbusters (1984) "SFX Team Featurette" (1999) (DVD ts. 05:44-06:03). Columbia Pictures. Annick Therrien says: "So I would end yo y'know printing image down and on a cell I would use a repeatograph at #0-0-0-5-0, whatever small and outline frame by frame each character and paint in black... shoot in bottom light. It took 3 weeks to do like 1... 1-2 seconds."