Location-Distribution with Dedicated Warehouses

4 Location-Distribution with Dedicated Warehouses (Srinivasan, 2010) 

In Example 5.5, we allowed multiple deliveries to a customer. In other words, a customer can receive his demand from more than one warehouse. Suppose the customers demand single deliveries. In this case, each customer has to 

To guarantee that customer 1 receives supply from one of the sites only, we write the constraint  

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