This boundary is known as the Bullen discontinuity, or sometimes as the Lehmann discontinuity. A few years later, in 1940, it was hypothesized that this inner core was made of solid iron; its rigidity was confirmed in 1971. The outer core was determined to be liquid from observations showing that compressional waves pass through it, but elastic shear waves do not â or do so only very weakly.
Flannery Literary is a Chicago area literary agency representing writers of books for children and young adults because the most interesting, well-written, and time-honored books are written with young people in mind.
Other contact info. 1  Please contact my agent Elana Roth Parker at Laura Dail Literary Agency, Inc. for any rights inquiries or serious business.  Librarians and educators, media contacts, and event/festival planners, please email my publicist if you have questions: olivia [dot] russo [at] harpercollins [dot] com.