Rockingham County: economic and social; a laboratory study at the University of North Carolina, Department of Rural Economics and Sociology,

"Sources of information": leaf at end.

Statutes of Columbia College and its associated schools

Title varies

Geologic and water-supply reports and maps : Maryland-Delaware-District of Columbia.

Mode of access: Internet.

Report of the Provincial Fisheries Dept.

Mode of access: Internet.

Organochlorine pesticides and PCBs in aquatic ecosystems of the Central Columbia Plateau.

Mode of access: Internet.

Pesticides in public supply wells of the Central Columbia Plateau.

Mode of access: Internet.