A common scenario is to let swagger-php generate a definition based on your model class.
These definitions can then be referenced with `ref="#/components/schemas/$classname"
<br />
<b>Fatal error</b>:  Uncaught Error: Class 'UsingRefs\Model' not found in /var/www/productscrm.egodev1.info/data/www/productscrm.egodev1.info/releases/126/vendor/zircote/swagger-php/Examples/using-refs/Product.php:14
Stack trace:
#0 {main}
  thrown in <b>/var/www/productscrm.egodev1.info/data/www/productscrm.egodev1.info/releases/126/vendor/zircote/swagger-php/Examples/using-refs/Product.php</b> on line <b>14</b><br />