Extract purchase order data.

The output will include the following top-level fields:
- Purchase order date (DD/MM/YYYY format when unambiguous)
- Delivery date (DD/MM/YYYY format when unambiguous)
- Purchase order number (separated by a dash after every 4 digits)
- Supplier number
- Shipping address (Format: company name, street number, postal code, city, country)

Also, the output will include the data for each line item. 

For each line item, extract these scalar fields:
- Item number (e.g., 010, 020)
- Complete description 
- Quantity (text string including the unit, e.g., "8.600 LB") 
- Price per currency
- Material number