Australia: Aerogramme with Enclosure Returned to Sender for Additional Postage

Sent from Daylesford (28 SE 83) to Finland. Boxed „UNDERPAID / Postage collected from sender“ and single-line „Contains an enclosure“ handstamps.
 
Taxed as a short-paid air mail letter, for which the applicable rate was 75 c in 1983. 39 c missing postage collected from the sender.