Collaborators  
<br>
<br>

<b> on the  N-body problem, </b>
<br>
&nbsp <b> Since 2020 </b>
	<br>
<A HREF='http://www.math.umn.edu/~rmoeckel/'>
Rick Moeckel </A> U. of Minn.  
<br>


<A HREF='https://en.www.math.fau.de/mathematical-physics/prof-dr-andreas-knauf/'>Andreas Knauf </A> , University of Erlangen–Nuremberg
<br>
<A HREF="https://www.ceremade.dauphine.fr/~fejoz"> Jacques Fejoz </A> U.   Paris  Dauphine
<br>


&nbsp <b>  before 2020</b>
<br>
<A HREF='http://www.imcce.fr/Equipes/ASD/person/chenciner/'>
Alain Chenciner </A> Bureau des Longitudes et Paris 7 
<br>

 


<A HREF='http://www.maths.usyd.edu.au/u/dullin/'> Holger Dullin </A> U. of Sydney, Australia

<br>
<A HREF="https://www.ceremade.dauphine.fr/~fejoz"> Jacques Fejoz </A> U.   Paris  Dauphine
<br>
<A HREF='http://www.clas.kitasato-u.ac.jp/~fujiwara'>Toshiaki  Fujiwara </A> Kitasato University

<br>

<A HREF='https://www.researchgate.net/profile/Andrea-Venturelli-2'>Andrea Venturelli </A> U of Avignon, France

<br>

<A HREF ='https://www.mathgenealogy.org/id.php?id=32483'> Joseph Gerver </A>
 

<br>
<A HREF='https://ca.wikipedia.org/wiki/Carles_Sim%C3%B3_i_Torres'>
Carles Simo </A> Barcelona
<br>

<A HREF='http://www.unca.edu/faces/faculty/sam-kaplan'> Sam Kaplan </A> U. of North Carolina, Asheville
<br>


<A HREF='https://www.marklevimath.com/'> Mark Levi </A> Math., Penn State
<br>

<A HREF='https://www.matem.unam.mx/~hector/'>Hector Sanchez Morgada </A> UNAM, Mexico

<br>
<A HREF = 'https://arxiv.org/search/math?searchtype=author&query=Jackman,+C'> Connor Jackman </A> Heidelberg (as of 2024)

<br>
<br>

<b> On other subjects </b>
<br>
<A HREF='
http://www.cimat.mx/~gil/'>
Gil Bor </A>
CIMAT, Guanajuato, Mexico
<br>

<A HREF='https://en.wikipedia.org/wiki/Susan_P._Holmes'>
Susan Holmes </A>
Stanford,  Statistics Dept.
<br>

<A HREF='https://en.wikipedia.org/wiki/Persi_Diaconis/'>
Persi Diaconis </A>
Stanford, Math Dept,  Statistics Dept.

<br>
 
<A HREF='http://faculty.tmcc.edu/kehlers/'>Kurt Ehlers</A>  Truckee Meadow's Community College, California
<br>



<A HREF='http://epge.fgv.br/en/faculty/jair-koiller'> Jair Koiller </A>  Rio de Janeiro
<br>



<A HREF='https://sites.google.com/view/enricoledonne/home'>Enrico LeDonne </A>  University of Fribourg, Switzerland.
 

<br>
<A HREF='https://www.researchgate.net/profile/Yuri-Sachkov''> Yuri Sachkov </A>
  Russian Academy of Sciences
  <br>

<A HREF='https://www.researchgate.net/profile/Andrei-Ardentov'> Andrei Ardentov  </A>,  Russian Academy of Sciences. 
<br>

<A HREF ='https://de.wikipedia.org/wiki/Vladimir_S._Matveev'>Vladimir Matveev </A> U. of Jena, Germany


 
<br> Jih-Hsin Cheng, Institute of Mathematics, Taipei Office, Taiwan, R
<br>
<A HREF='https://arxiv.org/search/math?searchtype=author&query=Marugame,+T'> T Marugame  </A>  Osaka U. , Japan
 


<br>
<A HREF='http://staff.math.su.se/shapiro/'>Boris Shapiro </A> U. of Stockholm

<br>


<A HREF='http://www.math.technion.ac.il/~mzhi/main.html'>
Michail Zhitomirskii </A>
Technion, Haifa.
<br>
<A HREF='http://wagner.ucsc.edu/'> Onuttom Narayan </A> Physics, UCSC.

<br>



<A HREF="https://hybrid.soe.ucsc.edu/biblio"> Ricardo Sanfelice </A> Computer Science and Engineering, UC Santa Cruz