TY - JOUR ID - 145038048 TI - Internal migration and the changing structure of employment in the United States in 1900 : machine readable census samples as a new source for historical research PY - DB - UniCat KW - DEMOGRAPHIE KW - METHODOLOGIE KW - DEMOGRAPHIE KW - METHODOLOGIE UR - https://www.unicat.be/uniCat?func=search&query=sysid:145038048 AB - ER -