Hilgert, Joachim. “Applications of Lie Semigroups in Analysis.” In The Analytical and Topological Theory of Semigroups, edited by K.H. Hofmann and et al. Berlin: De Gruyter, 1990.

Hilgert, Joachim, and K.H. Hofmann. “On the Causal Structure of Homogeneous Manifolds.” Math. Scand. 67 (1990): 119–44.

Hilgert, Joachim, and K.H. Hofmann. “Compactly Embedded Cartan Algebras and Invariant Cones in Lie Algebras.” Advances Math. 75 (1989): 168–201.

Hilgert, Joachim. “A Note on Howe’s Oscillator Semigroup.” Ann. Inst. Fourier 39 (1989): 663–88.

Hilgert, Joachim, K.H. Hofmann, and J.D. Lawson, eds. Lie Groups, Convex Cones, and Semigroups. Oxford: Oxford University Press, 1989.

Hilgert, Joachim. “Spectrally Ordered Lie Algebras.” In Group Theoretical Methods in Physics, edited by H.D. Doebner and et al., Vol. 313. Lecture Notes in Physics. New York: Springer, 1988.

Hilgert, Joachim. “Invariant Lorentzian Orders on Simply Connected Lie Groups.” Arkiv För Mat. 26 (1988): 107–15.

Hilgert, Joachim, and K.H. Hofmann. “Classification of Invariant Cones in Real Lie Algebras.” Bull. AMS 11 (1988): 441–46.

Hilgert, Joachim, and K.H. Hofmann. “Invariant Cones in Lie Algebras.” Semigroup Forum 37l. Semigroup Forum, 1988, 241–52.

Hilgert, Joachim. “Maximal Semigroups and the Support of Gauss-Semigroups.” In Probability and Baysian Statistics, edited by R. Viertl. New York: Plenum Press, 1987.

Hilgert, Joachim. “Maximal Semigroups and Controllability in Products of Lie Groups.” Archiv Math. 49 (1987): 189–95.

Hilgert, Joachim, and K.H. Hofmann. “Invariant Cones in Real Lie Algebras.” In Aspects of Positivity in Functional Analysis, edited by R. Nagel and et al. North Holland, 1986.

Hilgert, Joachim. “The Mayer-Vietoris and the Puppe Sequence in K-Theory for C*-Algebras.” Studia Math. 83 (1986): 97–104.

Hilgert, Joachim, and K.H. Hofmann. “On the Automorphism Group of Cones and Wedges.” Geom. Dedicata 21 (1986): 205–17.

Hilgert, Joachim, and K.H. Hofmann. “On Sophus Lie’s Fundamental Theorem.” J. Funct. Anal. 67 (1986): 1–27.

Hilgert, Joachim, K.H. Hofmann, and J.D. Lawson. “Controllabilty of Systems on Nilpotent Lie Groups.” Beiträge Alg. Geom. 20 (1985): 185–90.

Hilgert, Joachim, and K.H. Hofmann. “Semigroups in Lie Groups, Semialgebras in Lie Algebras.” Trans. AMS 288 (1985): 481–504.

Hilgert, Joachim, and K.H. Hofmann. “Lorentzian Cones in Real Lie Algebras.” Monatshefte Math. 100 (1985): 183–210.

Hilgert, Joachim, and K.H. Hofmann. “Lie Semialgebras Are Real Phenomena.” Math. Ann. 270 (1985): 97–103.

Hilgert, Joachim, and K.H. Hofmann. “Old and New on SL(2).” Manuscripta Math. 54 (1985): 17–52.