1897-1899
[biblio collection='improvement-era' date='1897-01-01 to 12/31/1899' sort="year"]
1900-1909
[biblio collection='improvement-era' date='1900-01-01 to 12/31/1909' sort="year"]
1910-1919
[biblio collection='improvement-era' date='1910-01-01 to 12/31/1919' sort="year"]
1920-1929
[biblio collection='improvement-era' date='1920-01-01 to 12/31/1929' sort="year"]
1930-1939
[biblio collection='improvement-era' date='1930-01-01 to 12/31/1939' sort="year"]
1940-1949
[biblio collection='improvement-era' date='1940-01-01 to 12/31/1949' sort="year"]
1950-1959
[biblio collection='improvement-era' date="1957-01-01 to 12/31/1959" sort="year"]
1960-1969
[biblio collection='improvement-era' date="1960-01-01 to 12/31/1969" sort="year"]
1970
[biblio collection='improvement-era' date="1970-01-01 to 12/31/1970" sort="year"]