Trac #26623: add global entries for pending cone catalog citations.

The forthcoming sage.geometry.cone_catalog module will cite a few new
references,

  * [BV2009] Stephen Boyd and Lieven Vandenberghe.
  * [GJ2016] Muddappa Seetharama Gowda and Juyoung Jeong.
  * [GS2010] Daniel Gourion and Alberto Seeger.
  * [HS2010] Rene Henrion and Alberto Seeger.
  * [IS2005] Alfredo Iusem and Alberto Seeger.
  * [Jeong2017] Juyoung Jeong.
  * [SS2016] Alberto Seeger and David Sossa.

This commit adds those to the global list in references/index.rst to
ensure that the cone catalog documentation can be built right away.

src/doc/en/reference/references/index.rst

@@ -1122,6 +1122,11 @@ REFERENCES:
             :doi:`10.1016/j.dam.2003.06.002`
             http://jl.baril.u-bourgogne.fr/derange.pdf
 
+.. [BV2009] Stephen Boyd and Lieven Vandenberghe.
+            Convex Optimization.
+            Cambridge University Press, Cambridge, 2009.
+            ISBN 9780521833783.
+
 .. [BvR1982] Andries Brouwer and John van Rees,
              More mutually orthogonal Latin squares,
              Discrete Mathematics,
@@ -2269,6 +2274,11 @@ REFERENCES:
 .. [GJ2007] \A. Glen, J. Justin, Episturmian words: a survey, Preprint,
             2007, :arxiv:`0801.1655`.
 
+.. [GJ2016] Muddappa Seetharama Gowda and Juyoung Jeong.
+            Spectral cones in Euclidean Jordan algebras.
+            Linear Algebra and its Applications, 509:286-305, 2016.
+            :doi:`10.1016/j.laa.2016.08.004`.
+
 .. [GJKPRSS2019] \D. Goudarzi, J. Jean, S. Koelbl, T. Peyrin, M. Rivain, Y. Sasaki, S. M. Sim.
                  "Pyjamask"
                  https://csrc.nist.gov/CSRC/media/Projects/Lightweight-Cryptography/documents/round-1/spec-doc/Pyjamask-spec.pdf
@@ -2415,6 +2425,12 @@ REFERENCES:
 .. [GS1999] Venkatesan Guruswami and Madhu Sudan, Improved Decoding of
             Reed-Solomon Codes and Algebraic-Geometric Codes, 1999
 
+.. [GS2010] Daniel Gourion and Alberto Seeger.
+            Critical angles in polyhedral convex cones: numerical and
+            statistical considerations.
+            Mathematical Programming, 123:173-198, 2010.
+            :doi:`10.1007/s10107-009-0317-2`.
+
 .. [Go1993] David M. Goldschmidt.
             *Group characters, symmetric functions, and the Hecke algebras*.
             AMS 1993.
@@ -2704,6 +2720,12 @@ REFERENCES:
             Mathematische Zeitschrift 105(2): 110-113, 1968.
             :doi:`10.1007/BF01110435`.
 
+.. [HS2010] Rene Henrion and Alberto Seeger.
+            Inradius and Circumradius of Various Convex Cones Arising in
+            Applications.
+            Set-Valued and Variational Analysis, 18(3-4):483-511, 2010.
+            :doi:`10.1007/s11228-010-0150-z`.
+
 .. [HS2018] \B. Hutz, M. Stoll. "Smallest representatives of
             `SL(2,\ZZ)`-orbits of binary forms and endomorphisms of P1",
             :arxiv:`1805.08579`, 2018.
@@ -2806,6 +2828,11 @@ REFERENCES:
             Modern Number Theory*, Springer-Verlag, GTM volume
             84, 1990.
 
+.. [IS2005] Alfredo Iusem and Alberto Seeger.
+            On pairs of vectors achieving the maximal angle of a convex cone.
+            Mathematical Programming, 104(2-3):501-523, 2005.
+            :doi:`10.1007/s10107-005-0626-z`.
+
 .. [ISSK2009] \M. Izadi, B. Sadeghiyan, S. S. Sadeghian, H. A. Khanooki,
               *MIBS: A new lightweight block cipher*; in
               CANS, (2009), pp. 334-348.
@@ -2836,6 +2863,10 @@ REFERENCES:
 .. [Jet2008] \D. Jetchev. Global divisibility of Heegner points and
              Tamagawa numbers. Compos. Math. 144 (2008), no. 4, 811--826.
 
+.. [Jeong2017] Juyoung Jeong.
+               Spectral sets and functions on Euclidean Jordan algebras.
+               University of Maryland, Baltimore County, Ph.D. thesis, 2017.
+
 .. [JK1981] Gordon James, Adalbert Kerber,
             *The Representation Theory of the Symmetric Group*,
             Encyclopedia of Mathematics and its Applications, vol. 16,
@@ -4769,6 +4800,11 @@ REFERENCES:
               J. Combin. Theory Ser. A, **133** (2015) pp. 29-75.
               :arxiv:`1404.6539`.
 
+.. [SS2016] Alberto Seeger and David Sossa.
+            Critical angles between two convex cones I. General theory.
+            TOP, 24(1):44-65, 2016.
+            :doi:`10.1007/s11750-015-0375-y`.
+
 .. [SS2017] Ben Salisbury and Travis Scrimshaw.
             *Rigged configurations for all symmetrizable types*.
             Electron. J. Combin., **24(1)** (2017) #P1.30. :arxiv:`1509.07833`.