Besides looking at ancient scrolls, the multispectral scanner can compare things like bank notes and passports with reference documents of known provenance.

ECONOMIST: Monitor

She finds herself obliged to eschew notes and research and reference books.

ECONOMIST: English memoirs

Whereas Mr Stora's points of reference for the war are usually French and often cultural (he notes the blossoming of French cinema and the opening of the first supermarkets), Mr Wall's are international and geopolitical.

ECONOMIST: Algeria then and now