The solution is composed of the following projects:
• Web form application
• UnitTest application
• Class libraries where I defined the layers of the application.
Domain layer
Services layer
Business layer
Presentation layer
I am using the Model first approach to generate the database and
classes.  This model is located in the domain layer project and it is
called "Model2".
The test project was useful to test the validity of the model.
In week four I created the interfaces for all domain objects with stub
implementations. I also created the Factory class and implemented the
search books use case.
In week five I refactored the Factory to use a single method to
instantiate all services using the new implementation of the
presentation lecture.  I also created the App configuration file and the
base Marker interface.  Moreover I implemented the first manager class
BooksMgr, which I use to search for books in the database using from one
to three search parameters.  I am planning to implement two new
use-cases next week.