Columbia subject headings:
Border patrols--California--San Diego.
Foreign workers, Mexican--California--San Diego.
Mexicans--California--San Diego.
Police patrol--California--San Diego.
Undercover operations--California--San Diego.
Harvard subject headings:
Border patrols--California--San Diego.
Foreign workers, Mexican--California--San Diego.
Mexicans--California--San Diego.
Police patrol--California--San Diego.
Undercover operations--California--San Diego.
Princeton subject headings:
Border patrols--California--San Diego.
Foreign workers, Mexican--California--San Diego.
Mexicans--California--San Diego.
Police patrol--California--San Diego.
Undercover operations--California--San Diego.