This includes the complete 6-volume reference guide, reference documents, a general index, Britannica International Maps, and four years of the International Yearbook (1976, 1977, 1978, and 1979). The complete 20-volume Britannica International Encyclopedia is listed separately as item ①, so please be sure to purchase it together. --- Due to its age, there is some yellowing and light soiling on the outside, but I feel that the inside of the books is clean. There appear to be no writings or graffiti, but there are many volumes, so I haven't been able to check everything. Please forgive any oversights, insufficient explanations, or differences in perception. Please consider purchasing if you understand that these are used books and that they are being sold with some scratches and stains. Please see my profile. Please refrain from price reductions. I will ship them directly in a cardboard box via Yu-Pack cash-on-delivery, in two packages. I am not responsible for any accidents, non-delivery, or damage during shipping. The items will be shipped with simple packaging. Compensation is as per the carrier's regulations. Due to circumstances, my replies and responses may be delayed.