83197
In 1988 , he extended this idea ( with Amos Fiat and Moni Naor ) to allow offline transactions that enable detection of double-spending .
 Amos Fiat, Moni Naor
Please list all entity words in the text that fit the category. Output format is "word1, word2". 
Option: media, plant, vehicle, astronomical object, time, disease, animal, location, person, organization, mythical figure, food, biology, geographical phenomenon, instrument, event 
Text: {0} 
Answer:
 Amos Fiat, Moni Naor