How to represent a duplicate data store in a data flow diagram (DFD) using Yourdon DeMarco notation?

While searching for the answer, I found that in the Gane & Sarson notation, duplicate data stores are indicated by adding an extra line. Another website suggested adding an asterisk next to the data store name. However, I was unable to find any answers specific to the Yourdon DeMarco notation.

Is there a generally accepted way to represent duplicates in the Yourdon DeMarco notation? Or should I adopt one of the methods stated above?