Public Domain Digitized Books and Articles:

Fort Halifax - Its Projectors, Builders And Garrison (1876)
The Winslow Register (1904)

Illustrated History of Kennebec County, Maine (1892) - Part I
Illustrated History of Kennebec County, Maine (1892) - Part II

Maine:  A History, Vol. I (1919) - Maine Historical Society
Maine:  A History, Vol. II (1919) - Maine Historical Society
Maine:  A History, Vol. III (1919) - Maine Historical Society

Books:

Dawn Over The Kennebec - Mary Calvert
The Kennebec Wilderness Awakens - Mary Calvert
Rivers of Fortune - Bill Caldwell
Kennebec, Cradle of Americans - Robert P. Tristram Coffin

Websites and Facebook Pages

Winslow Historical Preservation Committee on Facebook
Winslow Historical Preservation Committee contributions on Maine Memory Network
Fort Halifax Park Master Plan