Foldon fusion of RBD and S1 fragments of SARS‐CoV‐2 to stabilize the structure of subunit protein as a vaccine candidate oleh Gracia Christine Lembong Purwanto, Fedric Intan Damai, Dian Fitria Agustiyanti, Popi Hadi Wisnuwardhani, Alfi Taufik Fathurahman, Yana Rubiyana, Ratna Dwi Ramadani, Muhammad Khairul Lisan Sidqi, Pekik Wiji Prasetyaningrum, Endah Puji Septisetyani, Dadang Supriatna, Ratih Asmana Ningrum, Wien Kusharyoto, Ihsan Tria Pramanda, Andri Wardiana