PAL

Ptolemaeus Arabus et Latinus

_ (the underscore) is the placeholder for exactly one character.
% (the percent sign) is the placeholder for no, one or more than one character.
%% (two percent signs) is the placeholder for no, one or more than one character, but not for blank space (so that a search ends at word boundaries).

At the beginning and at the end, these placeholders are superfluous.

Grundlagen ‘model’

German

References: PH Nix: I.1:1, 71:5
Translation of:
Arabic: الأصل [PH Morelon: I.1:1, 15:4]
Synonyms:
Grundlage[PH Nix: I.2:4, 73:35]