Perhaps you should try some spelling variations:
integration theories » integration theory, integration through, integration efforts
grid integration » trade integration, _ integration, data integration
case irrigation » scale irrigation, change irrigation, canal irrigation
supply grid » supply crowd, support grid
supply case » supply cost, supply chain, supply curve
systems. » system.

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: (( supply grid integration theories. ) or ( supply case irrigation systems. ))~.
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