Many of Beyoncé's collaborators in Lemonade's long list of credits aren't collaborators at all. Her sixth album makes strategic use of samples and interpolations, wedding older references and new, with a purposefulness that transforms the source material into something fresh. Under-sung Southern hip-hop anthems and critically hailed rock stars are both raw tools to be subsumed into the most ambitious project of Beyoncé's career. Here is the what, why and how of Lemonade's many ingredients.