Thai Hung, Ngo, Quyen, Huynh, Quynh, Vo, Trang, Tran, AND Nhu, Huynh. " Return and Volatility Spillover Effects between Bond, Stock, Oil, and Gold Markets in Vietnam: Evidence from the Pre- and During the COVID-19 Period" VNU JOURNAL OF ECONOMICS AND BUSINESS [Online], Volume 2 Number 5 (25 October 2022)