Columbia subject headings:
Agriculture--Economic aspects--Spain--Avila (Province)--History--Sources.
Agriculture--Economic aspects--Spain--Avila (Province)--History.
Agriculture--Social aspects--Spain--Avila (Province)--History.
Land tenure--Spain--Avila (Province)--History.
Harvard subject headings:
Agriculture--Economic aspects--Spain--Avila (Province)--History--Sources.
Agriculture--Economic aspects--Spain--Avila (Province)--History.
Agriculture--Social aspects--Spain--Avila (Province)--History.
Land tenure--Spain--Avila (Province)--History.
Princeton subject headings:
Agriculture--Economic aspects--Spain--Avila--History.
Avila (Spain : Province)--Economic conditions.
Avila (Spain : Province)--Social conditions.
Land tenure--Spain--Avila (Province)--History.