Q: In this task, you're given a passage, further information available on a particular linked term from the statement, and an answer term. Your job is to generate a question that can use the information provided to obtain the given answer. You should use the information on both passage and link information to create the question. Note that the answer to the question should be exactly the given answer, and if the answer is none, the answer to the question shouldn't be obtainable from the passage or linked information.
Passage: In 1979 Hirschfeld published the first of a trilogy on Galois geometry, pegged at a level depending only on "the group theory and linear algebra taught in a first degree course, as well as a little projective geometry, and a very little algebraic geometry." When q is a prime power then there is a finite field GF(q) with q elements called a Galois field. A vector space over GF(q) of n + 1 dimensions produces an n-dimensional Galois geometry PG(n,q) with its subspaces: one-dimensional subspaces are the points of the Galois geometry and two-dimensional subspaces are the lines. Non-singular linear transformations of the vector space provide motions of PG(n,q). The first book (1979) covered PG(1,q) and PG(2,q). The second book addressed PG(3,q) and the third PG(n,q). Chapters are numbered sequentially through the trilogy: 14 in the first book, 15 to 21 in the second, and 22 to 27 in the third. Finite geometry has contributed to coding theory, such as the Goppa code, so the field is supported by computer science. In the preface of the 1991 text Hirschfeld summarizes the status of Galois geometry, mentioning maximum distance separable code, mathematics journals publishing finite geometry, and conferences on combinatorics featuring Galois geometry. Colleague Joseph A. Thas is coauthor of General Galois Geometries on PG(n,q) where n 4.
Link Information: Galois geometry (so named after the 19th century French Mathematician Evariste Galois) is the branch of finite geometry that is concerned with algebraic and analytic geometry over a finite field (or Galois field). Answer: Galois geometry

A:
When was the type of geometry Hirschfeld published about in 1979 first invented?