Foundations of Relative Category Theory / 3. The Grothendieck construction [0009] / 3.2. Displayed categories from functors [000B] / [001W] Exercise 3.2·c. Verify that $\TotCat{P\Sub{\bullet}}\to E$ is a categorical equivalence. Exercise 3.2·b [001V] Section 3.2.1. Relationship to Street's fibrations [000C]