The first instance of this expression in a historiographic context appears to be the famous but until now inaccessible Lo rgyus chen mo ("Grand Annals") by Khu ston brTson 'grus g.yung drung (1011-1075).11 The expression lo rgyus, literally "tidings of year[s]," is only very occasionally best rendered by "annals." It is far more often the case that works with this term in their title do not fulfill what[page 43] is promised by such a rendition, that is to say, they do not at all give a year-by-year account of their subject-matter, but rather present a narrative of events, historical, quasi-historical, or even ahistorical, in rough chronological sequence. It is well known that later historiographic sources abound in quotations from what appears to be Khu ston's work, although it does not seem to be extant.12 The fragments indicate that it was largely, if not entirely, written in verse. dPa' bo also often availed himself of this work in his study of Tibet's imperial period, and it functioned, for example, as one of his fundamental sources for information about the decades after Emperor Glang dar ma's assassination in 842 (or 846, the year which he assigns to this event), specifically about the insurrection of 869 against his two sons, 'Od srung and Yum brtan, which spread from central to eastern and northeastern Tibet (see DPA'1: 429-430; DPA': 432-433).