class ParentPoco
{
    public string Id { get; set; }
    public List<ChildPoco> Children { get; set; }
    public string Name { get; set; }
}
class ChildPoco
{
    public string Id { get; set; }
    public List<GrandChildPoco> GrandChildren { get; set; }
}
class GrandChildPoco
{
    public string Id { get; set; }
}

TypeAdapterConfig<ParentPoco, ParentDto>.NewConfig()
    .PreserveReference(true);

TypeAdapterConfig<ParentPoco, ParentDto>.NewConfig()
    .PreserveReference(true);
TypeAdapterConfig<ChildPoco, ChildDto>.NewConfig()
    .PreserveReference(true);
TypeAdapterConfig<GrandChildPoco, GrandChildDto>.NewConfig()
    .PreserveReference(true);

TypeAdapterConfig.GlobalSettings.Default.PreserveReference(true);

TypeAdapterConfig<ParentPoco, ParentDto>.NewConfig()
    .Fork(config => config.Default.PreserveReference(true));

TypeAdapterConfig<ParentPoco, ParentDto>.NewConfig()
    .Fork(config => config.ForType<string, string>()
        .MapToTargetWith((src, dest) => string.IsNullOrEmpty(src) ? dest : src)
    );