William M. Ramsay’s book, The Church in the Roman Empire Before AD 170 is now available for free download in PDF. The map facing p.472 of the Lycus Valley in particularly useful and is reproduced at various resolutions.
The following public domain book is now available on-line in PDF: Elmer Truesdale Merrill [1860-1936], Essays in Early Christian History. London: MacMillan & Co., Ltd., 1924. Hbk. pp.334. Click <<HERE>> for the download link.