This scale measures how likely a customer buying one product is to also purchase additional products based on a salesperson's recommendation. Burchett, Murtha, and Kohli (2023) used it across two studies examining secondary selling beyond the salesperson-customer dyad.
Burchett, Molly R., Brian Murtha, and Ajay K. Kohli (2023), "Secondary Selling: Beyond the Salesperson–Customer Dyad," Journal of Marketing, 87 (4), 575-600.
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