/**
 * @fileoverview Utility for extracting the publication/source name from a
 * document's `og:site_name` meta tag or class-based markers.
 */
/**
 * Extract source from document using common class names
 *
 * @param {document} document document or dom object with article content
 * @returns {object} source
*/
export declare function extractSource(document: any): any;