Many years ago I bought this book -
"Princess Diana: The Hidden Evidence"
I lent it out and never got it back.
There is a review of it here-
[Princess Diana: The Hidden Evidence] Book review by Stephen Reid
"One such 'unnamed' source - a former SAS sergeant - reveals that the 'accident' in which Diana died bore all the tell-tail signs of a known special forces assassination technique known as the 'Boston brakes'. Agreed, on first hearing, this sounds a bit James Bond - contrived. But bear with it. Because then you go on to read the testimony of former SAS officer and world famous explorer, Sir Ranulph Fiennes, who confirms that the 'Boston brakes' is indeed a commonly employed assassination technique used by hired 'hit squads', and that it involves the use of a device which remotely controls the target-vehicle's steering and brakes. Fiennes goes on to say that this method has been used at least once in England, and in this regard describes in some detail the assassination of one Major Michael Marman, who was killed in a 'car crash' near Stonehenge in 1986. There's no doubt that the operation that killed Major Marman, as described by Fiennes, as well as by former Equerry to the Queen, Air Marshall Sir Peter Horsley, was chillingly identical to the series of events that killed Diana. Once again I have to say that the way the authors are able to continually corroborate their evidence in this way, throughout the book, is very impressive. "