“Solved and unsolved problems of structural chemistry” by Milan Randić, Marjana Novič, and Dejan Plavšić CRC Press, Boca Raton, 2016, XX+472 pp. ISBN 13‐978‐1‐4987‐1151‐7

The present book apparently looks like the work of three authors, and possibly it is so by circumstance, but in fact presents the development of the mathematical and theoretical subjects, which had been the obsessions along the scientific life of the main author: Milan Randi c. Along 14 chapters and a large number of appendices (23!), the volume quite well printed by CRC Press essentially develops the problems related with the connection of graph theory with molecular structure and chemistry. An introduction provides a nice presentation of several problems (solved and unsolved) issued along the history of mathematics. Next, in a didactic way the authors’ ideas about mathematical chemistry and initial developments of the use of chemical graphs are presented. More recent problems related with molecular structure and activity, the development of molecular descriptors and partial ordering, associated to molecular graphs are also (why not?) present in the middle of the treatise. The final chapters deal with similarity, aromaticity, and bioinformatics. A final chapter about Beauty in Science as well as Beautiful Problems ends the book. In several places the authors (the spirit of the main author is the inspiration of this part, no doubt) complain about the difficulties the theory (promoted mainly by Croatian scientists, now extended around the world) has faced to grow the extended mathematical corpus, which constitutes the present volume backbone. It is historically interesting that such complaints appear somewhere, in company of the printed documentation of some nasty comments of scientific journal referees and officials. Everyone trying to develop new scientific concepts and novel results, which in more or less intensity could enrich the scientific lore, possibly has suffered such incidents. Sometimes one wonders how fellow scientists can be so harsh with the work of others, even if they feel that a refereed paper might be wrong. Scientific development could turn boring though, if difficulties at the publishing stage completely disappear. Might be the written witness of the difficulties encountered by Randi c along his successful career can be an example about how to circumvent them. Finally it is interesting to note that the book presents and discuss some problems from a point of view based on graph theory and the deduced parameters from it. I refer to StructureProperties Relations essentially. Many alternative aspects and problems appear absent in the book, possibly because the authors did not work on other ways or were uninterested by alternative points of view to look at QSPR. Of course, they cannot complain, if the promoted book features are in turn ignored by others. The present commentator has had the chance to read the two versions of the book: electronic and printed. The electronic version in some places has some flaws when downloading a page. Might be the program provided has some problems by itself or this reader did not manage well the reading flow. The book is interesting enough to be worth reading and alternatively constitutes quite an important consulting tool.