The six hundred and thirtieth volume of the Archives of Maryland Online series is The Counties of Maryland,
Their Origin, Boundaries, and Election Districts, by Edward B. Mathews,
originally published in 1906. The Archives of Maryland volume was published in 2003.
Edward Bennett Mathews. The Counties of Maryland, Their Origin, Boundaries, and Election Districts.
Maryland Geological Survey (Reports) V. 1906.
The color plates included as part VI are reproduced in Edward C. Papenfuse and Joseph M. Coale III, The Maryland
State Archives Atlas of Historical Maps of Maryland, 1608-1908 (Baltimore: The Johns Hopkins University Press, 2003) as
Figs. 12-17, 20, 31, 46, 52-53, 64, 94-95, 104, and 171.