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    Hajja, Mowaffaq
      (with S. Abu-Saymeh) Triangle centers with linear intercepts and linear subangles, 5 (2005) 33--36.
      (with S. Abu-Saymeh) Some Brocard-like points of a triangle, 5 (2005) 65--74.
      (with M. Spirova) A characterization of the centroid using June Lester's shape function, 6 (2006) 53--55.
      A very short and simple proof of ``the most elementary theorem" of euclidean geometry, 6 (2006) 167--169.
      (with S. Abu-Saymeh) Coincidence of centers for scalene triangles, 7 (2007) 137--146.
      A short trigonometric proof of the Steiner-Lehmus theorem, 8 (2008) 39--42.
      A condition for a circumscriptible quadrilateral to be cyclic, 8 (2008) 103--106.
      (with S. Abu-Saymeh and H. A. ShahAli) Another variation of the Steiner-Lehmus theme, 8 (2008) 131--140.
      Stronger forms of the Steiner-Lehmus theorem, 8 (2008) 157--161.
    Hatzipolakis, Antreas
      (with F. M. van Lamoen, B. Wolk, and P. Yiu) Concurrency of four Euler lines, 1 (2001) 59--68.
      (with P. Yiu) Pedal triangles and their shadows, 1 (2001) 81--90.
      (with P. Yiu) Reflections in triangle geometry, 9 (2009) 301--348.
    Haugland, Jan Kristian
      A note on conic sections and tangent circles, 17 (2017) 1--12.
    Helfgott, Michel
      (with G. Baloglou) Angles, area, and perimeter caught in a cubic, 8 (2008) 13--25.
    Hererra, Blas
      Two conjectures of Victor ThŽbault linking tetrahedra with quadrics, 15 (2015) 115--122.
    Hess, Albrecht
      A highway from Heron to Brahmagupta, 12 (2012) 191--192.
      Bicentric quadrilaterals through inversion, 13 (2013) 11--15.
      On a circle containing the incenters of tangential quadrilaterals, 14 (2014) 389--396.
      Transforming tripolar into barycentric coordinates, 15 (2015) 253--261.
      (with D. Perrin and M. Trense) A group theoretic interpretation of Poncelet's theorem -- the real case, 16 (2016) 381--395.
      A group theoretic interpretation of Poncelet's theorem, part 2: the complex case, 17 (2017) 255--272.
    Hoehn, Larry
      A new formula concerning the diagonals and sides of a quadrilateral, 11 (2011) 211--212.
      The isosceles trapezoid and its dissecting similar triangles, 12 (2012) 29--38.
      Derivation of the law of cosines via the incircle, 13 (2013) 133--153.
    Hoffmann, Miklos
      (with S. Gorjanc) On the generalized Gergonne point and beyond, 8 (2008) 151--155.
    Hofstetter, Kurt
      A simple construction of the golden section, 2 (2002) 65--66.
      A 5-step division of a segment in the golden section, 3 (2003) 205--206.
      Another 5-step division of a segment in the golden section, 4 (2004) 21--22.
      Division of a segment in the golden section with ruler and rusty compass, 5 (2005) 135--136.
      A 4-step construction of the golden ratio, 6 (2006) 179--180.
      A simple ruler and rusty compass construction of the regular pentagon, 8 (2008) 61--62.
      A simple compass-only construction of the regular pentagon, 8 (2008) 147--148.
    Holland, inbarr
      Another verification of Fagnano's theorem, 7 (2007) 207--210.
    Holshouser, Arthur
      (with H. Reiter) Using complex weighted centroids to create homothetic polygons, 12 (2012) 247--251.
      (with S. Molchanov and H. Reiter) Applying Poncelet's theorem to the pentagon and the pentagonal star, 16 (2016) 141--149.
      (with S. Molchanov and H. Reiter) A special case of Poncelet's problem, 16 (2016) 151--170.
    Homentcovschi, Laurentiu
      (with W. G. Boskoff and B. D. Suceava) Gossard's perspector and projective consequences, 13 (2013) 169--184.
    Honvault, Pascal
      (with T. Gensane) Optimal packings of two ellipses in a square, 14 (2014) 371--380.
      Similarities on a sphere, 16 (2016) 313--316.
    Horwitz, Alan
      A ladder ellipse problem, 16 (2016) 63--67.
    Hudelson, Matthew
      Concurrent medians of (2n+1)-gons, 6 (2006) 139--147.
      Formulas among diagonals in the regular polygon and the Catalan numbers, 6 (2006) 255--262.
    Hurley, Susan
      (with A. Fontaine) Proof by picture: Products and reciprocals of diagonals length ratios in the regular polygon, 6 (2006) 97--101.
    Hvala, Bojan
      Diophantine Steiner triples and Pythagorean-type triangles, 10 (2010) 93--97.
    Hwang, Minyoung
      (with C. W. Bae and J. H. Lee) Some loci in the animation of a Sangaku diagram, 16 (2016) 187--191.