@inbook{f3c4e8d12b3d4b6f99af21b5f3c6282d,
title = "Tools for the GHP Formalism",
abstract = "After the introduction of the NP formalism, Geroch, Held and Penrose developed the so-called GHP calculus (Geroch et al. 1973). In their own words: Often this choice [of the tetrad] has to be made arbitrarily to some extent since the geometry of the situation may not define that much structure at each point in a natural way.",
author = "Pedro Bargue{\~n}o and Ernesto Contreras",
note = "Publisher Copyright: {\textcopyright} The Author(s), under exclusive license to Springer Nature Switzerland AG 2023.",
year = "2023",
doi = "10.1007/978-3-031-42948-4_4",
language = "Ingl{\'e}s",
series = "SpringerBriefs in Physics",
publisher = "Springer VS",
pages = "25--34",
booktitle = "SpringerBriefs in Physics",
}