163051
In all but Tanenbaum 's last seven novels , he credits Michael Gruber , his cousin , as a collaborator , and Gruber is generally considered as being Tanenbaum 's ghostwriter .
 person: Tanenbaum; person: Michael Gruber; person: Gruber; person: Tanenbaum
Given options, please tell me the categories of all the listed entity words.Output format is "type1: word1; type2: word2". 
Option: location, person, organization 
Text: {0} 
 Entities: Tanenbaum, Michael Gruber, Gruber, Tanenbaum 
Answer:
 person: Tanenbaum; person: Michael Gruber; person: Gruber; person: Tanenbaum