(center (frame :border 1 :margin 2 :width 90. (processor :engine (make-engine '_ :filter string-upcase) :combinator (lambda (e1 e2) (let ((e (copy-engine '_ e2))) (markup-writer '&bib-entry-ident e :action (lambda (n e) (let* ((be (ast-parent n)) (o (markup-option be 'author)) (y (markup-option be 'year))) (output (markup-body o) e1) (display ":") (output (markup-body y) e)))) (markup-writer '&bib-entry-title e :action (lambda (n e) (skribe-eval (it (markup-body n)) e))) e)) (the-bibliography :pred (lambda (m n) (eq? (markup-option m 'kind) 'book))))))