RECTOR ORBIS
AVG Laureate head with bare bust of Didius Julianus to the right.
The emperor standing on the left, holding a globe with the right hand and a scroll with the left hand.
Photo of a coin sold the 21/03/2007 by Numismatica Ars Classica, Auction 38, lot 92, link to the sale: https://www.acsearch.info/search.html?id=363045, link to their website:https://www.arsclassicacoins.com/.
All aurei seen with the obverse legend IMP CAES DID IVLIANVS AVG and bare bust share the same obverse die. This die is associated with several different reverse dies for each type. It is therefore associated with the types: CONCORD MILIT, P M TR P COS and RECTOR ORBIS.
The dot between IVLIAN and AVg is very little, other coins confirm its existence more clearly.
For the aurei, the RIC mentions for the type P M TR P COS: bust (a) (this one) as well as a laureate bust with drapery over the left shoulder (b) and a laureate and draped bust (c) for this type. I did not find these the last bust which probably exist somewhere but one can wonder if it is not a mistake. Indeed, the RECTOR ORBIS type is given with a bust (a) and (b) but not for the (c). However I found for this type the bust (a) and (c)... The coin quoted ''Ponton d'Amécourt Sale, April 25th, 1887, lot 371'' as bust (b) is in reality a bust (c). See comments and photos of AYC #5 B, RIC 3 var.