Lake Youngs SL #4 - Making cut for Petrovitsky Rod Ext. - East of Shadow Lake Rd 190th SE - b/w prints with 35 mm negs, 1974-02-22, Box: 20, Folder: 10573. Water Department Photographic Negatives, 8200-13. Seattle Municipal Archives. https://leglas100/finding-aids/repositories/2/archival_objects/199913 Accessed June 02, 2026.