sow-keys

Including the basic AMPS library:

using AMPS.Client;
using AMPS.Client.Message;
using AMPS.Client.Exceptions;

Constructing the command:

Command cmd = new Command(Message.Commands.SOW)
                  .setTopic(topic)

                  // Key string contains AMPS sow keys
                  .setSowKeys(comma_delimited_key_string)
              ;

The command can now be used in execute or executeAsync.