BrickLink - Part 2685b : LEGO Monorail Coupling Long (Sets 6399 / 6991) [ Monorail] - BrickLink Reference Catalog
Vintage LEGO 6399 Airport Shuttle Monorail Train classic set from 1990 - YouTube
BrickLink - Part BA006pb11 : LEGO Stickered Assembly 4 x 1 x 3 with Classic Airport Logo Pattern on Both Sides (Stickers) - Set 6399 - 3 Brick 1 x 4 [Stickered Assembly] - BrickLink Reference Catalog
REVIEW: 6399 Airport Shuttle - LEGO Town - Eurobricks Forums
LEGO 6399 Airport Shuttle 100% Complete With Instructions See Notes! – Pihtat
BrickLink - Part 4760c00pb05 : LEGO Electric 9V Battery Box Small Without Battery Cover with Airport Shuttle Pattern on Both Sides (Stickers) - Set 6399 [Electric, Battery Box] - BrickLink Reference Catalog
6399 Airport Shuttle from BrickLink Studio
BrickLink - Part 2572pb03 : LEGO Panel 6 x 6 x 9 Curved Top with Shuttle Route Map Pattern on Inside (Sticker) - Set 6399 [Panel, Decorated] - BrickLink Reference Catalog