pocket83's suggested procedure for treating musty books~
0) Risk.
This is not a professional restoration procedure. The following should be applied only after cost/benefit considerations. Damage may be incurred to books of extreme age and/or rarity through this method. As such, apply these steps only to those books that might otherwise be destroyed.
1) Dry.
Remove all moisture from the book first. Don't try to heal the wound without removing the bullet. Drying a damp book will require splaying the pages out and exposing them to airflow. In bad weather, a dehumidifier's output fan is one source for warm, dry air. Keep temperature moderate and consistent if possible. Just as fresh-cut wood must not be cured too quickly, so too with a wet book; with wet paper, a slow steady moisture reduction will best preserve the original shape of the wood pulp. Sunlight dries quickly, but it is also dramatic: for this reason, it is better to apply sun at step #5.
2) Clean.
Physically remove all visible mildew from the book by using baking soda as an abrasive. Yank the bullet. Throw away the used powder. Next, put the book into a bucket and splay out its pages. Sprinkle an entire box of baking soda over the top, gently knocking the pile down and into the spaces between the pages. Try to have some small amount between each page. Don't cover the bucket. Though airflow will be limited inside of a bucket, it's best if air circulation can still continue above it. Allow book to remain this way for as long as you can tolerate.
3) Sawdust.
Now we treat the smell. Steps 1 & 2 were mostly about stopping the decomposition process, but exposing a musty book to sawdust is about making it once again waft of fresh wood pulp. Be sure that your sawdust is dry. That might sound obvious, but lumber can really contain lots of moisture. If you haven't already stored away a bucket of clean sawdust a few weeks ago, then I suggest you air out a fresh pile in the sunlight now, before you proceed. If you're reading this lab procedure before starting (like you're supposed to), then you have the time to dry out some sawdust as your book is being dried and cleaned. Oh, yeah-step 3. Simply put the book in the bucket again, splay the pages, and cover it all with sawdust. Allow book to remain this way for as long as you can tolerate.
4) Air.
Remove all baking soda and sawdust from the book. To get the insides, position the book so that its spine faces up, and then gently agitate the pages with air. The pages face down, so direct the air down too, just like a comb is while you're combing your hair. Compressed air will work quickly, but it will also be aggressive on the pages. For this reason, limit how often you use compressed air over this entire process; try to remember that small amounts of damage are cumulative. For a more cautious approach, apply a gentle fan to the top edge of the book, and just allow any remaining powder to fall out over the course of time. One last time, allow book to remain this way for as long as you can tolerate.
5) Sun.
Expose the book to sunlight. Again, splayed pages will maximize the surface area of exposure. Remember, sunlight is a source of heat, so apply it with caution. Too much exposure to the sun will end up causing its own damage, so use moderation. Think of this step as being like baking brownies: you can't bake them any faster by turning up the oven without sooner scorching them.
6) Scent.
Covering up an odor is not an elimination of the odor. But it's still nice, and it does chase off any pesky remnant. Baby powder is mild and pleasant, and the corn starch variety has the added benefit of further smell-removal.
7) Rinse and repeat.
Don't actually rinse the book. That was a metaphor. Sure, I know by the nature of the fact that you're reading this that you're probably literate enough to've realized it, but I have to say it anyway. Just repeat the above steps (especially the sawdust and air treatments) until you're satisfied with the result. At some point, there will be a diminished return, sure. But with enough sawdust and patience, even the most stubborn, smelliest book is going to eventually smell like fresh-cut wood again.