Studi Awal Pengembangan Vaksin Subunit: Karakterisasi Molekular, Pengklonaan Gen dan Ekspresi Protein Rekombinan VP6 Rotavirus Strain Indonesia Genotipe I (R55) dan II (R10) = A Preliminary Study of Subunit Vaccine Development: Molecular Characterization, Gene Cloning, and Expression of Recombinant protein VP6 of Rotavirus Strains Indonesia Genotype I (R55) and II (R10)