The authors have written neither a book nor a paper, but something in between, and as a result the first half of the book is pretty heavy going.
Progress has been made; it was heavy going, but we succeeded in moving ahead.
However, the topics dealt with are often esoteric methodological ones which will make the book heavy going for all except a few specialist demographers.
Sometimes the venerability makes this book heavy going.
The non-specialist may find the book's technical terms and subtle discourse heavy going.
They will find it very heavy going indeed.
Other unexplained technical terms make this chapter heavy going, and even the text that attempts to link the mathematics to biology does not flow nor did it maintain my attention.
Indeed, he found it pretty heavy going, to put it mildly.
