Columbia subject headings:
Agriculture--Economic aspects--Spain--Castilla la Vieja.
Castilla la Vieja (Spain)--Rural conditions.
Harvard subject headings:
Agriculture--Economic aspects--Spain--Castilla la Vieja.
Castilla la Vieja (Spain)--Rural conditions.
Princeton subject headings:
Agriculture--Economic aspects--Spain--Bureba-Ebro Region--History.
Agriculture--Economic aspects--Spain--Castilla y Leon--History.
Land tenure--Spain--Bureba-Ebro Region--History.
Land tenure--Spain--Castilla y Leon--History.