&gt; Do you have any other recommendations?<p>You might take a look at www.amazon.com&#x2F;Rapid-Development-Taming-Software-Schedules&#x2F;dp&#x2F;1556159005&#x2F;. Although it&#x27;s 20 years old, it has some good ideas in it. It&#x27;s also more about 6-month estimations than 90-minute estimations, though.