Wcf Linq Serialization Error

An error occurred while receiving the HTTP response to http://localhost:8732/Design_Time_Addresses/WcfServiceLibraryTest/GenreService/.
This could be due to the service endpoint binding not using the HTTP protocol.
This could also be due to an HTTP request context being aborted by the server (possibly due to the service shutting down).
See server logs for more details.

There was an error while trying to serialize parameter http://tempuri.org/:ListGenresResult.
The InnerException message was 'Object graph for type 'System.Data.Linq.EntitySet`1[[DataLayer.Musician, DataLayer, Version=1.0.0.0, Culture=neutral, PublicKeyToken=null]]' contains cycles and cannot be serialized if reference tracking is disabled.'.

Solution:
Serialization Mode : Unidirectional (dbml file)

WCF Logging:
http://msdn.microsoft.com/en-us/library/ms732009.aspx
http://msdn.microsoft.com/en-us/library/ms730064.aspx

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