Final two lectures of Neville's 1964 series
Date (happened)
between 11 December 1964 and 15 December 1964
unresolved
between 11 December 1964 and 15 December 1964
relative · preferred
Why
Class B multi-delivery set; linked deliveries remain separate.
Reasoning
The source lecture was certainly delivered Tuesday 1964-12-08 and explicitly identifies the remaining deliveries as Friday and next Tuesday, yielding 1964-12-11 and 1964-12-15. The event represents both deliveries as a Class B set, so a bounded range records the set without merging either delivery.
Told / reported
8 December 1964
estimated
Reasoning
Passage 546400 belongs to lecture nid 1840, whose preserved dateline establishes delivery on 1964-12-08 with certain confidence.