For those who like to learn from videos, here is an interview/lesson from Carl Hewitt (he introduced the model): https://www.youtube.com/watch?v=7erJ1DV_Tlo ht

For those who like to learn from videos, here is an interview/lesson from Carl Hewitt (he introduced the model): https://www.youtube.com/watch?v=7erJ1DV_Tlo https://www.youtube.com/watch?v=7erJ1DV_Tlo