Zelda: Link's Awakening Trading Sequence guide: how to get the Boomerang by swapping items | RPG Site
Zelda: Link's Awakening trading sequence quest: Where to trade the Yoshi Doll, Ribbon, Dog Food, Bananas and other items for the Magnifying Lens | Eurogamer.net
How to complete the trading quest in Link's Awakening | iMore
Link's Awakening trade up to get the Magnifying Glass and Boomerang walkthrough - Polygon
The Legend Of Zelda Link's Awakening What the Magnifying Glass Is For (Quick Tips) - YouTube