Census of India, 1951 <br/><br/>
Working population in Calcutta industrial region-distribution by industry place of birth and education attainment 1951 census. 

 - West Bengal  Bengal Govt. Press          1951 
<br/><br/><label>Source: </label> General Book 
<br/><br/><label>Dewey Class. No.: </label>Y:5.275sN51, J5.6