| Perubahan Garis Pantai Desa Bentenan Kecamatan Pusomaen, Minahasa Tenggara ET Opa Jurnal Perikanan dan Kelautan Tropis 7 (3), 109-114, 2011 | 46 | 2011 |
| Karakteristik sedimen litoral di pantai Sindulang Satu JIS Korwa, ET Opa, R Djamaludin J. Pesisir dan Laut Tropis 1 (1), 48-54, 2013 | 25 | 2013 |
| Analisis perubahan luas lahan mangrove di kabupaten Pohuwato propinsi Gorontalo dengan menggunakan citra Landsat ET Opa Jurnal Perikanan dan Kelautan Tropis 6 (2), 79-82, 2010 | 23 | 2010 |
| Karbon pada padang lamun di perairan pulau manado tua MA Maramis, B Wagey, AP Rumengan, CFA Sondak, ET Opa, KFI Kondoy Jurnal Pesisir dan Laut Tropis 8 (2), 79-91, 2020 | 10 | 2020 |
| Community structure of mangrove in Mantehage Island and Paniki Island, North Sulawesi, Indonesia ET Opa, JD Kusen, RC Kepel, A Jusuf, LJL Lumingas Aquaculture, Aquarium, Conservation & Legislation 12 (4), 1388-1403, 2019 | 9 | 2019 |
| Arah dan kecepatan arus perairan sekitar Pulau Bunaken pada periode umur bulan perbani di musim pancaroba II R Modalo, R Rampengan, E Opa, R Djamaluddin, H Manengkey, ... Jurnal Pesisir dan Laut Tropis 6 (1), 61-68, 2018 | 9 | 2018 |
| Ecological suitability of mangrove ecotourism in Labuan Uki Bay, Bolaang Mongondow Regency, North Sulawesi Province, Indonesia R Lasabuda, AV Lohoo, ET Opa Advances in Environmental Sciences 11 (1), 41-50, 2019 | 8 | 2019 |
| Ecological suitability of mangrove tourism in Mantehage Island as the outermost small island in North Sulawesi, Indonesia ET Opa, RC Kepel, R Lasabuda, JD Kusen, CP Paruntu, R Djamaluddin, ... Aquaculture, Aquarium, Conservation & Legislation 14 (1), 120-129, 2021 | 7 | 2021 |
| The potential of marine ascidians as sources of natural antioxidant and antibacterial agents from Manado, North Sulawesi DA Sumilat, JR Rimper, ET Opa, D Kurnia Aquaculture, Aquarium, Conservation & Legislation 12 (1), 373-377, 2019 | 6 | 2019 |
| Characteristic of Litoral Sediment on Sindulang Satu Coastal JIS Korwa, ET Opa, R Djamaludin Jurnal Pesisir dan Laut Tropis 1 (1), 48-54, 2013 | 3 | 2013 |
| Perubahan Luas Lahan Mangrove ET Opa Jurnal Perikanan dan Kelautan 2, 2010 | 3 | 2010 |
| Morfologi Gisik Pantai Desa Kalasey Satu Kecamatan Pineleng Kabupaten Minahasa WFF Sasauw, HWK Manengkey, ET Opa Jurnal Pesisir dan Laut Tropis 1 (2), 1-5, 2013 | 2 | 2013 |
| FORAMINIFERA PADA LAHAN GISIK DI PANTAI MALALAYANG DUA P Billy, JM Mamuaja, RM Rampengan, M Ompi, ET Opa, J Mudeng | 1 | |
| Sediment Granulometry of the Beach at the Kalasey’s Groynes R Simboh, RM Rampengan, HWK Manengkey, R Djamaluddin, ET Opa, ... Jurnal Ilmiah PLATAX 9 (2), 234-246, 2021 | | 2021 |
| Study of meiobenthos community in Manado Beach, North Sulawesi AB Windarto, RM Rampengan, ET Opa, SB Pratasik AACL Bioflux 14 (2), 2021 | | 2021 |
| MORFOMETRI GISIK KAWASAN PANTAI WISATA BAHARI SARIO KOTA MANADO Z Otoluwa, R Djamaluddin, RM Rampengan, J Mamuaya, ET Opa, ... JURNAL PESISIR DAN LAUT TROPIS 9 (2), 35-42, 2021 | | 2021 |
| KAJIAN SOSIAL EKONOMI NELAYAN ALAT TANGKAP JUBI PADA ERA NEW NORMAL DI DESA KAHAKITANG KECAMATAN TATOARENG KABUPATEN KEPULAUAN SANGIHE PROVINSI SULAWESI UTARA L Jamin, VEN Manoppo, N Jusuf, FV Longdong, LK Rarung, ET Opa AKULTURASI: Jurnal Ilmiah Agrobisnis Perikanan 9 (1), 33-41, 2021 | | 2021 |
| Foraminifera On The Beach Of Malalayang Dua P Billy, JM Mamuaja, RM Rampengan, M Ompi, ET Opa, J Mudeng Jurnal Ilmiah PLATAX 6 (2), 114-123, 2018 | | 2018 |
| Antibacterial Activity of PvBa-RL8 Isolate, Bacterium Associated with Nudibranchia Phyllidia varicosa RAJ Lintang, DA Sumilat, ET Opa COMMITTEE, 41, 0 | | |
