English determination method or standard: SHA-1...
a derivative work of the following images: File:Blas Cabrera - Principio de relatividad (figura 1).jpg licensed with PD-old, PD-scan 2022-09-29T01:31:40Z...
a derivative work of the following images: File:Blas Cabrera - Principio de relatividad (figura 3).jpg licensed with PD-old, PD-scan 2023-08-11T21:08:26Z...