The source article gives a well-dated instance (The 1969 Warner/Reprise Songbook, a discounted compilation album used to promote the label's roster) but that is a documented APPLICATION of the tactic in the record industry, not its origin; the pricing tactic itself is understood to be far older in general retail, and the article names no earlier date or first use.
What would resolve this A retail-history or pricing-economics source giving a specific year or decade for the first documented use of below-cost pricing to draw store traffic, prior to the mid-20th-century instances that are commonly cited today.
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