Printed version available here
"Despite the considerable development that railway history has seen in these last three decades, there are still numerous aspects related to that process that are yet to be discovered and explored. This book by Dr. Luís Santos comes precisely to provide an important contribution to the knowledge of the implementation of the railway network among us in the period of 1884 to 1891, and in particular, the role played by one of its most prominent protagonists, Tristão Guedes de Queiroz Correia Castelo Branco, the Marquess of Foz, thus filling an important gap in Portuguese railway history.
Also in regard to the Tua line, the author presents in this work essential aspects related to the entire process that led to its realization. Although it was a minor investment in the universe of the Marquess of Foz's business, as he points out, it did not cease to be important in the strategy that he developed within the National Railway Company."
(From the preface, by Professor J.M. Lopes Cordeiro)