Best book about Pirc and Modern? From my side best are Pirc Alert by Alburt and Keene’s Pirc defence and Tiger’s modern by Hillarp Persson and Keene’s Modern defence.
Both Keene’s books are over 30year old, but are /mainly Modern defence/ full interesting IDEAS. Of course, all variantions are not correct, because during 30 year was founding improvements for one side, but still both books are intersting. Pirc Alert covered only small numbers variantions, but have high degree verbal explanation – long second part of book is probably best. I like it, i carefully read Pirc Alert three times. Tiger’s modern is full original analysis. But in this moment i think, that 4..a6 have big problems and i am looking for another opening.
Next very interesting book is Modern defence by Speelman /from Everyman
/. There is little problem /not first time/ - few games, comments or analysis are based /copy+paste/ on Keene’s book, but Speelman this fact mentioned.
Ultimate Pirc from McNab+Nunn and Videki‘s Pirc defence are full games or fragments. Lot of materials, but authors don’t share his own opinion and preferable continuation. Very interesting is one from latest interview with John Nunn /
http://www.chessbase.com/newsdetail.asp?newsid=3318/ , where he says: No, I think this type of book, this kind of encyclopedic book, there’s just no point anymore. The type of opening book that I used to specialize in… I think time for that is gone now. This is very important view.
Gallagher‘s Starting Out: Pirc defence is classical book from this serie. Lot of verbal explanation for target players below 2000. We need more special material
.
Modern defence by Dave Norwood is interesting book, but book have only „few“ pages and personaly included material i dont like very much.
Carpathian warrior by Lalic is interesting book, but covered mainly some special variations /or modern with 4.f4/ and i fear, than are not checked with computer, but are very inspiring
There is 3+4 book OFWATA – interesting concept based on 4.f4 against Pirc and Modern. I have really doubts about right evalution in this books.
Hippopotamus rises by Andrew Martin is clearly bad book. Maybe this was reason, why was Martin's Modern defence canceled by publisher.