Included here are correspondence, notes, shipping documents, bills and invoices, diagrams, and sketches related to each job. Artwork and photographs have been removed to the Drawings and Blueprints and Photographs series respectively. The arrangement of this series preserves Ravenna's original system, which generally files jobs in numerical order from earliest to latest. The first two numerals of the job number correspond to the last two numerals of the year in which the job was initiated. For example, job 5706 was undertaken in 1957. Exceptions to this chronological structure are the first folders dealing with jobs that never reached fruition and the last few folders, which have to do with suppliers of mosaic tesserae and with early mosaic jobs dating from the 1920s to the 1950s. Arrangement within folders is chronological; the exception, again, is some of the final folders, where items appear in reverse chronological order.