Paperbacks are the way to go,they fit the coatpocket too,though the confined space often wrecks
their shape and once buckled the individual pages can be lost. I've found that for a while this isn't
a problem: the first and last parts in a paperback are most regularly unnecessary for a reading of
the text. To lose the inner pages requires several days,often weeks. The fewer pages of a short book will go first has been my experience; bigger books seem to hang together longer...Unscientifically written,well that's nobody's business but mine,after all it is blog!