Linking sales orders to purchase orders

[tamaratamas9]

I have a list of purchase orders with multiple line items. I would need to get the sales order number for any of the line items if it exists. If the account assignment category for the purchase order line item is E, then there is a sales order number. This is what i would need to write a query for. So if the purchase order is in the list, i would need to get all of the related line items that have a sales order.

Thank you in advance