The type or namespace name 'IBM' could not be found (are you missing a using directive or an assembly reference?)

please help on below error 

Compilation Error

Description: An error occurred during the compilation of a resource required to service this request. Please review the following specific error details and modify your source code appropriately.

Compiler Error Message: CS0246: The type or namespace name 'IBM' could not be found (are you missing a using directive or an assembly reference?)

Source Error:

Line 27: using System.Web.Services;
Line 28: using System.Net;Line 29: using IBM.WMQ;Line 30: using System.DirectoryServices.AccountManagement;