WHO KILLED BARBARA ANN DERRY?

According to https://www.newspapers.com/article/54911436/barbara-ann-derry-body-found-1972/ , and to https://murderpedia.org/male.F/f/forrest-warren-leslie.htm , Barbara Ann Derry of Goldendale was last seen hitchhiking near State Route #14 of Vancouver in the State of Washington. The highway is located near the I-5 interchange, which also leads to Seattle after going through km 33 with the Wildwood exit. The victim was a student

WHO KILLED JAMIE ROCHELLE GRISSIM?

As reported by https://www.websleuths.com/forums/threads/wa-jamie-grissim-16-vancouver-7-dec-1971.77636/ , Jamie Rochelle Grissim disappeared into thin air on December 7, 1971 after going to the Fort Vancouver High School, located at 5700 East 18th Street in Vancouver, Washington near the Columbia River in order to replace the old Franklin School building. Some of the victim’s belongings and documents were found

D.B. COOPER: THE 1971 LETTERS

As reported by https://www.history.com/news/db-cooper-case-fbi-letters, a few days after Flight 305 was hijacked, D.B. Cooper sent some letters to the Reno Evening Gazette in Nevada. The hand of George Hill Hodel is immediately noticeable, which incorporates the style of newspaper clippings with coded messages already used as the Black Dahlia Avenger. In the November 29 letter,

D.B. COOPER IDENTIFIED/IDENTIFICATO D.B. COOPER

On November 24, 1971 (date with the sum of the digits equal to 8) D.B. Cooper (registered under the name of Dan Cooper, inspired by the cartoon by Belgian Albert Weinberg) boarded the Boeing 727 in Portland (the city of roses) as he took the flight no. 305 Northwest Airlines which was carrying 43 (4+3=7)