1. On the precision of age measurements by Rb-Sr isochrons in nontrivial cases

   • A. B. Vistelius
   • A. V. Faas

   OriginalPaper Pages: 999 - 1044

2. Confidence regions in ternary diagrams based on the power-divergence statistics

   • Frederick Medak
   • Noel Cressie

   OriginalPaper Pages: 1045 - 1057

3. Monitoring well placement using conditional simulation of hydraulic head

   • Dale H. Easley
   • Leon E. Borgman
   • Dennis Weber

   OriginalPaper Pages: 1059 - 1080

4. A plea for precision inMathematical Geology

   • John Aitchison

   Letter To The Editor Pages: 1081 - 1083

5. Comment on “Locating a Point on a Spherical Surface Relative to a Spherical Polygon of Arbitrary Shape” by Michael Bevis and Jean-Luc Chatelain

   • Douglas M. Hawkins

   Letter To The Editor Pages: 1085 - 1086

6. Reply to comments by Douglas M. Hawkins

   • Michael Bevis

   Letter To The Editor Pages: 1087 - 1088

7. Editor's note

   • Robert Ehrlich

   EditorialNotes Pages: 1089 - 1090