Menzel (1964) outlined three enduring themes that remain relevant today, even after 50 years, in providing services to scientists:
(A). Guiding Slogan of Speed, Efficiency, and Comprehensiveness:
(B). Prototype Activity of Exhaustive Search:
(C). Access User needs in digital environment.
(D). Achievement through Systematization, Streamlining, and Automation:
1
A, B and C
2
B, C and D
3
A, C and D
4
A, B and D