Burkholder, E. F. The 3-D global spatial data model: Principles and applications (Second edition.).
Čikaški stil citiranjaBurkholder, Earl F. The 3-D Global Spatial Data Model: Principles and Applications. Second edition.
MLA način citiranjaBurkholder, Earl F. The 3-D Global Spatial Data Model: Principles and Applications. Second edition.
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