Principles of x-ray crystallography by Li-ling Ooi is a brave entry into an area where there are a number of excellent short introductory texts (e.g. Crystallography Made Crystal Clear by Rhodes) as well as more definitive accounts (e.g. Principles of Protein Crystallography by Drenth, Biomolecular Crystallography by Rupp as well as the IUCr series which contain numerous excellent texts on all aspects of crystallography....etc etc).
Principles of x-ray crystallography is a frustrating read on two significant levels. First is the lopsided emphasis on units cells and space groups, whereas other aspects are delivered in one line of mathematics. Secondly, there are numerous errors which must seriously question whether this is sutable for the uninitiated.
In summary, I would direct new students of crystallography to other well-established texts.
Dr M. Crispin
Oriel College, Oxford