Nancy Drew books were an important part of my childhood. And I often checked them out from the public library. While the library in the town where I lived didn't have the entire collection, a nearby library did. I remember being overwhelmed by the yellow spined collection and selected based entirely on the cover picture. Eventually I owned some of my own Nancy Drew books. The Twin Dilemma was the first Nancy Drew purchase I made. While the yellow spined novels ended with #56, this later addition to the series added almost twenty books to the collection, and allowed Nancy to solver her mysteries in the late 1970s and early 80s.
I loved these books. I saved my pennies for these books. I waited until family vacations to Minneapolis to visit a large bookstore to make my purchases. I remember reading this entire book on the way home from Minneapolis, and stopping after each chapter, trying to make my enjoyment last longer.
This book introduced me to the word titian (Nancy's hair color), the name Eloise (Nancy's aunt), and created an excitement for series mysteries (which I am still known to read).