The study on Vietnamese claims to the Paracel Islands and Spratly Islands is incomplete and can not be justified without the study on the original and true geographic positions of the "Hoang Sa Archipelago" and "Truongsa Archipelago" - which are the titles today's Vietnam uses to refer to the Paracel Islands and Spratly Islands and claims to.
The limited information available on the "Quần đảo Hoàng Sa" and "Quần đảo Trường Sa" from modern Vietnamese language sources makes the study difficult, since historically Vietnamese history was recorded in Chinese language, the information from the mordern romanized Vietnamese language resources was specially selected by the Vietnamese government with the favor to support its claim on the "Hoang Sa" and "Truong Sa" islands. Thus the study of "Hoang Sa" and "Truong Sa" - their origins and their real original locations, requires a thorough study based on relevant historical archives in their original documents, be it in Chinese, English, French, Japanese, Vietnamese, or any other languages.
Since Vietnam started its claims on the Paracels and Spratlys, they have persisted in the argument that the "Hoang Sa islands" they had knowledge of (if it is true) refers to the internationally publicized "Paracels", while mere study was bothered to prove or question that these geographic names really refer to the same area. Similar is for the Vietnamese claims in the Spratlys.
A few important documents heavily referred to as the Vietnamese proclaimed to the Paracels and Spratlys are their diplomatic publications regarding this issule. These inlcude the White Paper on the Hoang Sa (Paracel) and Truong Sa (Spratly) Islands by Ministry of Foreign Affairs, Republic of Vientnam (South Vietnam) in Saigon in 1975; The Hoang Sa and Truong Sa Archipelagoes (Paracels and Spratlys) I and II published by Ministry of Foreign Affairs, Socialist Republic of Vietnam in 1981 and 1985 respectively. Some of the most important "historical documents and juridical evidence"[1, p6] which "unmistakingly proved" Vientnamese sovereignty over the two archipelagoes cited in these publications will be studied here.
One point needs to note is that the "historical documents" by Vietnam have no clear differentiation of the two archipelagoes. As pointed out by Dieter Heinzig, Vietnamese argumentation covering the period until the end of the 19th century, refers exclusively to the Paracels. The mere fact that in the early days of the January 1974 conflict the official Saigon media used the wrong names when trying to support their claims by reference to historical events makes the Vietnamese assertions appear somewhat dubious. [2, p24]. Unlike the Chinese side having historical maps and geographic names that differentiates the Xisha Islands and Nansha Islands more clearly than the Vietnamese. The Vietnamese sources use mixed terms to refer to these entities. As stated in the 1981 booklet, "In those days, the Vietnamese called the area Bai Cat Vang (Golden Sandbank) or Hoang Sa, or Van Ly Hoang Sa, or Dai Truong Sa or Van Ly Truong Sa as shown in ancient Vietnamese books and maps." Probably along with this in mind, following this it was stated that "Almost all Western navigators' maps between the 16th and 18th centuries marked these two groups of islands under one single name : Pracel or Parcel or Paracels"[1,p7]. Putting this way, it seems to implicate that the Vietnamese using mixed terms on mixed island groups should be acceptable and is quite similar to the early Western knowledge on the islands of South China Sea. But whether Western maps showing "Paracels, Paracel, Pracels" really refers to both "Paracel Islands and Spratly Islands", or is it at the time of drawing these maps, the westerners really didn't have knowledge on the Spratly Islands, this remained to be studied. It is groundless to simply conclude that "Hoang Sa" includes "Hoang Sa and Truong Sa Archipelagoes", As the Vietnamese have been unable to find evidence to prove their activities in Spratly Islands in remote times, by saying that the Hoang Sa included the two archipelagoes would provide them a ground to make a claim to Spraty Islands. [3, p161]
"...Notes accompanying the maps clearly indicate that as far back as the early 17th century, Vietnamese authorities had been saending, on a regular basis, ships and men to these islands, which at that time were named 《Cat Vang》(both 《Cat Vang》 and 《Hoang Sa》 mean 《yellow sand》). These are the islands now known internationally by the name 《Paracles》."
"At the village of Kim Ho, on both banks of the river, stand two mountains each containing a gold deposit exploited under government control. On the high sea, a 400-ly long and 200-ly large archipelago (2) called 《Bai Cat Vang》(Yellow sand banks) emerges from the deep sea facing the coastline between the harbour of Dai Chiem and the harbour of Sa Vinh (3). During the South-West monsoon season, commercial ships from various countries sailing near the coasts often wreck on the insular territories. The same thing happens during the North-East monsson season to those ships sailing on the high sea. All the people on board wrecked ships in this area would starve. Various kingds of wrecked cargoes are amassed on these islands. Each year during the last month of winter, the Nguyen rulers send to the the islands an 18-junk flottilla in order to salvage them. They obtain big quantities of gold, silver, coins, rifles and ammunitions. From the harbour of Dai Chiem the archipelago is reached after a journey of one-and-a-half day, while one day suffices if one embarks from Sa Ky (4).
(2) Ly is an ancient unit of measure (1 ly: 483 meters or 528
(3) Dai Chiem: present-day Cu'a Dai, province of Quang Nam, Sa Vinh: present-day Sa Huynh, province of Quang Ngai.
(4) The author assumedly include in the Hoang Sa archipelago many islands an reeefs closer to the Vietnamese shore than the islands islands designated as the Paracels in the 20th century. This explains why some islands could be reach in one day.
"Although geographical description of former tmes are not as precise as they are now, it is clear from the above that the yellow sand or Hoang Sa Islands have been part of the economic heritage of the Empire of Vietnam at least before 1653, the latest year when Do Ba could have completed his map drawing. Moreover, an eminent Vietnames hisotrian and scholar, Vo Long Te, has been able to determine that, taking into account other factors in the Do Ba's text (e.g. historical references and linguistic style), the salvage expeditions described therein actually started in the 15th century."
The question of allocating the name "Bai Cat Vang" to "Hoang Sa" without justification arised from this very first 1975 booklet, and the way Vietnam utilizing and interpreting this very first Document No 1. From here there is no further examination or research based on the locations, distances etc, but merely based on the meaning of the Chu Nam words "Cat Vang", Vietnam forcebly started to put "Cat Vang" onto what then (1975) Vietnam wanted to claim - the Hoang Sa islands, and continued to search for any "Cat Vang" in various books and documents to support its claim.
This document is the first and oldest Vietnamese document which mentioned the name "Bai Cat Vang", as it is stated in the 1975 booklet this book is "Evidence showing Vietnamese sovereighty over the Hoang Sa islands extends back over three hundred years". Let's study about its real locations based on the various information available.
... to be continued (last updated on Nov 25 2007)
 The Hoang Sa and Truong Sa Archipelagoes Vietnamese Territories, Ministry of Foreign Affairs, Socialist Republic of Vietnam, 1981
 Disputed Islands in the South China Sea: Paracels - Spratlys - Pratas - Macclesfield Bank, p24, Dieter Heinzig, Institute of Asian Affairs in Hamburg, 1976.
 Comment on Documents Claiming Vietnamese Sovereignty over the Spratly and Paracel Islands, CHEN HURNG-YU, Issues & Studies 35, no. 4 (July/August 1999); 149-185., p161
 White Paper on the Hoang Sa (Paracel) and Truong Sa (Spratly) Islands, Republic of Vietnam Ministry of Foreign Affairs, Saigon, 1975. pp16-18