ACKNOWLEDGEMENT
The authors would like to express
gratitude to the Vietnamese Ministry of Science
and Technology (MOST) conducted through the
Vietnamese-Chinese Program of Cooperation
in Science and Technology and the Vietnam
National Foundation for Science and Technology
Development (NAFOSTED), who fi nancially
supported the project, and to the DELPHE project
managed by the British Council to encourage
students to participate in activities of this study to
improve their research ability.