Iconscout - Design Resource Marketplace.
Design Principles - An open source repository of design principles and methods
Office Club Illustration pack - Whether you’re creating a website or mobile app, showcasing a portfolio, publishing a blog, or an e-commerce store — Office Club’s 100 illustrations and designed art directions help you create the best possible products.
UX Research Field Guide - Your map to the world of UX research 🌏🕵️♀️
Craftwork - A collection of User Interface resources made by Craftwork
Business-Driven Digital Product Design - A guide on how to create influential user experience