Custom text field for ticket classification

Custom text field for ticket classification

Hi, 

Is there a way to include a custom text field when assigning classifications to Zoho tickets?

We have 7-digit references we need to be able to include somehow in tickets for reporting purposes. This will help us classify tickets to individual customers. 

This would apply to both new tickets and existing ones in Zoho Desk.

Please let me know if you require further information