Both of these books heavily refer to some typical software development books: Design Patterns (Gang of Four), Refactoring (Martin Fowler), patterns of enterprise architecture (Martin Fowler), etc. Basically, these two books are trying to introduce concepts like design pattern, architecture, refactoring, which are common to java developers, to PHP. So, if you find these two books helpful, it is natural that the next step should be those reference books.
Both books introduce some common design patterns which may be used frequently in PHP development, for example, Factory, Singleton, Strategy, Observer, Composite, Command, Decorator.
However, I think both of them missed another important pattern: Delegate.
There are some other design patterns, which, based on my experience, are not often used in PHP development, are introduced in the two books. PHP In Action shows us Adapter, and the other book explain Interpreter.