The Belona Press booklet is ancient history, I doubt you could find it, but don't bother looking, there are much better, more modern titles for money. Achtung Panzer #1
Panzerkampfwagen IV, ISBN: 4-499-20532-8, covers all the variants of the Pz IV in detail, though the text is in Japanese.....but the line drawings are excellent and cover the smallest details, except no interior info. Euro Modelismo's
Compendium Modelling Manual #21, Panzer IV, ISBN: 1-902579-41-0, covers detailed builds of a PZ IV Ausf G, a Jagdpanzer IV L/70 and a Whirbelwind, with very nice color photos, a few paint schemes and museum shots. Squadron's
Panzer IV and
Panzer IV in Action, have many combat photos and several color plates, a good general reference, but not much for details. Schiffer Publishing's
Panzer IV and it's Variants, ISBN:0-88740-515-0, by Walter Spielberger, is the best reference for the Pz IV. Detailed and accurate drawings by Hillary Doyle and numerous photos, including interior shots, in it's 163 pages, has set the standard for many years. About $35. A must have book if you really want to get serious. Waldemar Trojca's
Sd.Kfz 161 Pz.Kpfw. IV Ausf G/H/J, ISBN: 83-60041-02-4 has very nice 1/35th scale drawings and several color plates, plus numerous photos, but no interior shots. Kagero Publishing also produces a very nice line of books, including one on the Pz IV, but I don't have it, so I can't tell you much about it.