Follow-up with the source by:
               
                  - 
                     
                        •
                        
                           mailing a letter to the source,
                           
                         
                      
                   
                  - 
                     
                        •
                        
                           faxing a letter to the source,
                           
                         
                      
                   
                  - 
                     
                        •
                        
                           calling and speaking to the source by telephone, or
                           
                         
                      
                   
                  - 
                     
                        •
                        
                           calling the source by telephone and leaving a clear and detailed message on the source's
                              voicemail.
                           
                           
                         
                      
                   
               
               Any of these contacts constitute a successful follow-up attempt with the source. For
                  more instructions on how to request and document receipt of evidence by telephone
                  or fax, see DI 22505.030.