Virginia DeMarce and Eric Flint wrote 1634: The Bavarian Crisis. It is the prequel to Grantville Gazettes.
[['1634: The Bavarian Crisis', 'PRECEDED_BY', 'Grantville Gazette III'], ['1634: The Bavarian Crisis', 'PRECEDED_BY', '"DeMarce short stories in the The Grantville Gazettes"'], ['1634: The Bavarian Crisis', 'AUTHOR', '"Virginia DeMarce and Eric Flint"']]