Dang Trinh Ky, Doctoral Thesis in Law (Paris, 1933), title : "Le nantissement des personnes dans l'ancien droit annamite"
("The debt-pawning of persons in ancient Annamese law")

Publisher : F. Loviton Domat-Montchrestien, Paris, 1933.
The Thesis was published later by les Editions Domat-Montchrestien (Paris,1933) under the title  "L'engagement des personnes en droit annamite"(
"The debt-pledging of  persons in Annamese law") with a preface of Professor René Maunier, in the series "Etudes de sociologie et d'ethnologie juridiques"("Studies in sociology and legal ethnology").

Full text of the Doctoral Thesis "Le nantissement des personnes dans l'ancien droit annamite",  PDF files, issued from the copy belonging to Mr Dang Trinh Ky's heirs  (these files may be downloaded for personal use):
Preliminary Chapter : Sources of slavery and the condition of slaves in the Annamese city 
(Les sources de l'esclavage et la condition des esclaves dans la cité annamite).
First Chapter : Causes and origin of the pawning of persons (Causes et origine du nantissement des personnes).
Chapter II : People who may be pledged as security for debt. Legal basis of the institution 
(Personnes susceptibles d'être placées en nantissement. Fondement juridique de l'institution).
Chapter IIII : Nature and conditions of the contract of pawning
(Nature et conditions du contrat de nantissement).
Chapter IV : Effects of the contract of pawning 
(Effets du contrat de nantissement).
Chapter V : Termination of the contract
(Extinction du contrat).
Chapter VI : A special case of pawning : the anomalous son-in-law
(Un cas particulier d'engagement pour dette : le gendre anomal).
Chapter VII : Attitude of the French legislator. Legislation and case law
(Attitude du législateur français. Législation et jurisprudence).

Availability in libraries : One or the two books may be found in various French libraries (ask the Catalogue collectif de France ) or American libraries  : Library of congress ,  Columbia, Harvard ( title 1 and  title 2) , Yale ( title 1 and  title 2), California, ...
The thesis has been microfiled as Microfiches by the foundation "Human Relations Area Files" with notes :
English translation also in Files : "The pledging of persons as security for debt in ancient Annamese law" 
( Human Relations Area Files collection of Ethnography – or HRAF– are considered as the largest ethnographic database in the world)