Welcome to the beginning of what some consider a disease. Good that you know where you want to start, kinda. If you are going to study the S84/98 III bayonet, this is a good place to start. We have THE bayonet guys here. As far as books, I think one or more of our members have published. I will tell you most of what you need to know can be learned right here. Every maker is listed. The codes are listed. There are pictures galore. Production numbers for each maker, for each year can be had. Read all you can and ask questions. If it is not written here, members will or should be able to answer any question. You need to figure out how you want to collect. Do you want one from each year, do you want one from each maker or do you want one from each maker for every year? Some collect certain makers, others certain years and some do it all. Better have deep pockets and lots of time if you want one example from each maker for each year. A daunting task for sure, but it can be done. It will not be easy, especially since there are more and more collecting every day. The S84/98 III has been a collectible item for a long time and with the increase in interest, sources are drying up. Six to seven years ago the amount of nice matching S84/98 III bayonets on Ebay were plentiful and for a fair price. Now matching ones are few and most of the sellers want to get rich from one bayonet. Good luck hunting and enjoy the disease.