I had hard time to find a second review for Ch. 2. Finally I've got it !  

Writing in Trends in Genetics, Khamlichi and Feil present a quick, yet exhaustive review of parallel mechanisms leading to all flavors of "Mono-allelic expression", which include imprinted genes (Genomic Imprinting),  X-chromosome inactivation, and other mono-allelic expression including Antigen Receptors, such as IgG and TCR in the immune system. 

We will discuss these phenomena tomorrow.