Ihor Radchenko writes: > Consider the following Org file: > > ------------ > [cite:@key] > #+print_bibliography: > That’s it! > ------------ > @key is not in the default bibliography and the bibliography processor is set to basic > > Open the file and execute C-c C-e t U (export to ascii) > > An error is thrown and export fails when attempting to print the > bibliography. The problem with error has been solved in another patch. However, the non-existing keys are exported awkwardly as "(, )". I suggest approaching the missing citations similar to LaTeX and highlight them with ??: (??, ????) by default. See the attached patch. WDYT?