APA

Wolter J. A., . (1986). World Directory of map collections. Munchen: K . G . Saur.

Chicago

Wolter John A, . 1986. World Directory of map collections. Munchen: K . G . Saur.

Harvard

Wolter J. A., . (1986). World Directory of map collections. Munchen: K . G . Saur.

MLA

Wolter John A, . World Directory of map collections. Munchen: K . G . Saur. 1986.