"All About Cockatiels" by Dr Gerald R Allen and Connie J Allen is a vintage reference book published in 1980 that provides in-depth information about cockatiels, a popular parrot species. This book serves as a valuable resource for bird enthusiasts and collectors looking to learn more about the characteristics, care, and behavior of these adorable creatures. With detailed insights and historical information, it is a must-have for anyone interested in the world of cockatiels and parrots in general.