I'm a fan of Seaby and Sear. Eric has been very helpful as well. But they pale in comparison to the amount of coins you can find online with acsearch, wild winds and CNG. Infinite space always beats finite space.
I'm with Ryro on this. I like the old, used one volume Sear for a book in hand but suggest online resources for more in-depth study. I have no problem with the more recent multivolume Sear books but they are expensive if you buy all five volumes. I do not recommend ERIC. https://www.amazon.com/gp/offer-lis...d_used_olp_sr?ie=UTF8&condition=used&qid=&sr= https://www.amazon.com/s/ref=nb_sb_...sprefix=sear+roman,aps,155&crid=3DFRFGRVQ347G