Exhibit 4
Joint Filing Agreement

Pursuant to Rule 13d-1(k) promulgated under the Securities Exchange Act of 1934, as amended, the undersigned hereby agree to the joint filing of this Statement on Schedule 13D, including any amendments thereto. This Joint Filing Agreement may be executed in any number of counterparts, each of which shall be deemed an original, but all of which shall constitute one and the same instrument.

This agreement may be executed in any number of counterparts, each of which shall be deemed an original.

October 25, 2018

   
GTRIMG Investments Ltd.
   
/s/ Gad Zeevi
   
Name: Gad Zeevi
Title: Chairman of the Board of Directors

   
TRIMG Communication International Ltd.
   
/s/ Gad Zeevi
   
Name: Gad Zeevi
Title: Chairman of the Board of Directors
 
   
GTRIMG Ltd.
   
/s/ Gad Zeevi
   
Name: Gad Zeevi
Title: Authorized Director
 
   
GTRIMG Foundation
   
/s/ I&R Administration AG
   
Name: I&R Administration AG, by Graf Francis Seilern-Aspbang
Title: Member of the Foundation Council
 
   
GTRIMG Foundation
   
/s/ I&R Administration AG
   
Name: I&R Administration AG, by Janine Grunenfelder
Title: Member of the Foundation Council
 
   
Establishment Elmana
   
/s/ Buehler Oswald
   
Name: Buehler Oswald
Title: Authorized Director