Cisco IOS images for GNS3

Found this link for huge collection of IOS images specifically for GNS3. 

Link 1

Note: None of these files is hosted by Certuniverse.

Cisco UCCX Student Guide

Cisco Unified Contact Center Express Official Student Guides. 

Ver - 2

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CVOICE Authorized Self-Study Guide - 4th Edition

Implementing Cisco Unified Communications Voice over IP and QoS (CVOICE) Foundation Learning Guide is a Cisco^®-authorized, self-paced learning tool for CCNP Voice foundation learning. Developed in conjunction with the Cisco CCNP Voice certification team, it covers all aspects of planning, designing, and deploying Cisco VoIP networks and integrating gateways, gatekeepers, and QoS into them.

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Note: This file is not hosted by Certuniverse.