<map name="Name" inverse="true">
	<key column="FirstID" />
	<index-many-to-many column="OtherID" class="OtherClass" />
	<one-to-many class="AnotherClass" />
</map>

private IDictionary<CurriculumSubject, SubjectCourse> subjectCourses;

public virtual IEnumerable<SubjectCourse> GetSubjectCourses() 
{
	return new SortedSet<SubjectCourse>(subjectCourses.Values, new SubjectCourseSorter());
}

public virtual HashSet<SubjectCourse> GetSubjectCourses() 
{
	return new HashSet<SubjectCourse>(subjectCourses.Values);
}

public virtual IEnumerable<SubjectCourse> GetSubjectCourses() 
{
	return new SortedSet<SubjectCourse>(subjectCourses.Values, new SubjectCourseSorter());
}

public class SubjectCourseSorter : IComparer<SubjectCourse> {

		public int Compare(SubjectCourse x, SubjectCourse y) {
			String[] code1 = x.Code.Split('.');
			String[] code2 = y.Code.Split('.');
			return int.Parse(code1[code1.Length-1])
				.CompareTo(int.Parse(code2[code2.Length-1]));
		}
	}