Original sentence: Histories of the princely states of Udaipur, Jodhpur, Bikaner, Dungarpur, Banswara and Pratapgarh were released over a twelve year period (1929-1941)
Edited sentence: Histories of the princely states of Udaipur, Jodhpur, Bikaner, Dungarpur, Banswara and Pratapgarh were successively released over a twelve year period (1929-1941)