- Instituto de Ecología y Sistemática (Academia de Ciencias de Cuba)
- Instituto de Ecología, A C.
- Instituto de Oceanología (Academia de Ciencias de Cuba)
- Instituto de Segunda Enseñanza de La Habana.
- Instituto Español de Oceanografía
- Instituto Físico-Geográfico Nacional (Costa Rica)
- Instituto Geográfico Argentino, Buenos Aires.
- Instituto Geográfico Argentino.
- Instituto Geológico de México
- Instituto Geológico de México.
- Instituto Histórico y Geográfico del Uruguay.
- Instituto Médico Nacional (Mexico)
- Instituto Oswaldo Cruz
- Instituto Tecnico di Novara.
- Instituut Voor Plantenziekten (Buitenzorg, Dutch East Indies)
- Instituut voor Plantenziekten en Cultures.
- Instrument Society of America Toronto and Los Angeles) 1961-
- Instrument Society of America.
- Instrument Society of America. Marine Sciences Division.
- Insunza, Bárbara
- Intake Water Company.
- Integrated Environments (2006) Ltd.
- Integrated Forest Pest Management Colloquium Pinchot Institute for Conservation Studies) 1978-
- Intera Environmental Consultants.
- Interagency Ad Hoc Task Force.
- Interagency BLM Aquatic Task Group.
- Interagency Burned Area Emergency Response Team (U.S.)
- Interagency Conference on Continental Shelf Research Coastal Engineering Research Center) 1965-
- Interagency Greater Sage-Grouse (U.S.). Disturbance and Monitoring Subteam.
- Interagency Grizzly Bear Committee (U.S.)
- Interagency Implementation Team.
- Interagency Wild and Scenic Rivers Coordinating Council.
- Interagency Workshop on In-Situ Water-Quality Sensing: Biological Sensors Pensacola Beach, Fla.) 1980-
- Inter-American Tropical Tuna Commission.
- Interesova, Elena A.
- Inter-Fluve, Inc.
- Intergovernmental Oceanographic Commission.
- Interián-Ku, Víctor Manuel
- Interior Columbia Basin Ecosystem Management Project (U.S.)
- Interior Nurseries (Perkinston, Miss.)
- Interior Nursery Company.
- Intermountain Forest and Range Experiment Station (Ogden, Utah)
- Intermountain Forest and Range Experiment Station (Ogden, Utah).
- Intermountain Forest Nursery Association.
- Intermountain Forest Nursery Association. Meeting Bismarck, N.D.) 1989-
- Intermountain Nursery Association.
- Intermountain Nursery Co.
- Inter-Mountain Nursery Co.
- Intermountain Nurseryman's Association.
- Intermountain Nurseryman's Association. Meeting Fort Collins, Colo.) 1985-
- Intermountain Nurseryman's Association. Meeting.
- Intermountain Outdoor Symposium Butte, Mont.) 1980-
- Intermountain Research Station (Ogden, Utah)
- International Arid Lands Meetings New Mexico) 1955-
- International Association for Plant Taxonomy
- International Association For Vegetation Science,
- International Association Of Bryologists.
- International Association of Geophysical Contractors.
- International Association of Instructors and Investigators in Poultry Husbandry.
- International Association of Tropical Agriculture and Colonial Development.
- International Atomic Energy Agency.
- International Billfish Symposium Kailua-Kona, Hawaii) 1972-
- International Botanical Congress Amsterdam, Netherlands) 1865-
- International Botanical Congress Antwerp, Belgium) 1885-
- International Botanical Congress Brussels) 1910-
- International Botanical Congress Brussels, Belgium) 1910-
- International Botanical Congress Brussels, Belgium). 1910-
- International Botanical Congress Genoa, Italy) 1892-
- International Botanical Congress Paris) 1867-
- International Botanical Congress Paris) 1878-
- International Botanical Congress Paris) 1900-
- International Botanical Congress Paris, France) 1867-
- International Botanical Congress Paris, France) 1878-
- International Botanical Congress Saint Petersburg, Russia) 1869-
- International Botanical Congress Vienna) 1905-
- International Botanical Congress Vienna, Austria) 1905-
- International Botanical Congress (2nd : Vienna, Austria) 1905-
- International Botanical Congress (5.º 1930. Cambridge, Reino Unido)
- International Bulb Society.
- International Bureau For Plant Taxonomy And Nomenclature
- International bureau of the American republics, Washington, D.C.
- International Bureau of the American Republics.
- International carneau club and pigeon association.
- International Carnivorous Plant Society.
- International Carnivorous Plant Society. Conference (2nd : Bonn, Germany) 1998-
- International catalogue of scientific literature.
- International Center for Arid and Semi-arid Land Studies.
- International Centre of Insect Physiology and Ecology.
- International Children's School Farm League.
- International Colloquium on the Biology of the Soricidae
- International Colloquium on Winter Ecology of Small Mammals Powdermill Nature Reserve, Rector, Pa.) 14-18 October 1981
- International Commission for the Northwest Atlantic Fisheries.
- International Commission for the Scientific Exploration of the Mediterranean Sea
- International Commission of Jurists (1952- )
- International commission on the control of bovine tuberculosis.
- International Commission on Zoological Nomenclature
- International Commission on Zoological Nomenclature. Secretariat.
- International Committee on Bacteriological Nomenclature.
- International Conference on Coelenterate Biology Noordwijkerhout) 16-07-1995 -21-07-1995
- International Conference On Na, K-Atpase Denmark) 1987-
- International Conference on Numerical Ship Hydrodynamics Paris) 1981-
- International Conference on Plant Growth Substances Yonkers, N.Y.) 1959-
- International Conference on plant hardiness and acclimatization New York, N.Y.) 1907-
- International Congress of Americanists (17th : 1910 : Buenos Aires, Argentina). Delegación Chilena
- International Congress of Americanists 1895 : Mexico City, Mexico)
- International Congress of Anthropological and Ethnological Sciences Zagreb, Croatia) 1988-
- International Congress of Arachnology Geneva, Switzerland) 1995-
- International congress of arts and science St. Louis) 1904-
- International Congress of Entomology Berlin, Germany) 1938-
- International Congress of Entomology Brisbane, Qld.) 2004-
- International Congress of Entomology Brussels) 1910-
- International Congress of Entomology Brussels, Belgium) 1910-
- International Congress of Entomology Canberra, A.C.T.) 1972-
- International Congress of Entomology Kyoto, Japan) 1980-
- International Congress of Entomology Oxford) 1912-
- International Congress of Entomology Washington, D.C.) 1976-
- International Congress of Entomology.
- International Congress of Genetics London, England) 1906-
- International Congress of Genetics New York) 1902-
- International Congress of Genetics Paris, France) 1911-
- International Congress of Genetics The Hague) 1963-
- International Congress of Genetics.
- International Congress of Histochemistry and Cytochemistry Paris) 1960-
- International Congress of Ophthalmology Utrecht, Netherlands) 1899-
- International Congress Of Soil Science Washington, D.C.) 1927-
- International Congress of Tropical Agriculture London) 1914-
- International congress of tropical agriculture. London, 1914-
- International congress of Tropical and subtropical agriculture. London, England) 1914-
- International Congress of Viticulture San Francisco) 1915-
- International Congress of Zoology (4th : 1898 : Cambridge, England)
- International Congress of Zoology Berlin, Germany) 1901-
- International Congress of Zoology Bern) 1904-
- International Congress of Zoology Cambridge, England) 1898-
- International Congress of Zoology Copenhagen, Denmark). 1953-
- International Congress of Zoology Monaco) 1913-
- International Congress of Zoology Moscow) 1892-
- International Congress of Zoology Paris) 1889-
- International Congress of Zoology. Graz, Austria) 1910-
- International Congress of Zoology. Leiden, Netherlands) 1895-
- International Congress of Zoology. Leyden, Netherlands) 1895-
- International Congress of Zoology. London) 1958-
- International Corbicula Symposium Little Rock, Ark.) 1983-
- International Correspondence Schools.
- International Council for Bird Preservation. Kenya Section.
- International Council for the Exploration of the Sea.
- International dry-farming congress.
- International Entomological Society.
- International Eugenics Congress New York) 1932-
- International Exhibition Cork, Ireland) 1902-
- International Exhibition London, England). 1883-
- International Federation of Cotton and Allied Textile Industries. International Cotton Mission to Brazil.
- International Field Year for the Great Lakes.
- International fisheries commision (U. S. and Great Britain)
- International fisheries commission (United States and Great Britain)
- International Fisheries Conference Detroit, Mich.). 1892-
- International Fisheries Exhibition
- International Fisheries Exhibition Edinburgh, Scotland) 1882-
- International Fisheries Exhibition Trondheim, Norway) 1908-
- International Fisheries Exhibition ( London, England) 1883-
- International Fisheries Exhibition (1898 : Bergen, Norway)
- International Fishery Congress Washington, D.C.) 1908-
- International fishery congress. 4th, Washington, 1908.
- International Forest Congress Paris, France) 1913-
- International Forestry Exhibition Edinburgh, Scotland) 1884-
- International Forestry Exhibition.
- International Garden Club.
- International Geological Commission.
- International Geological Congress Toronto) 1913-
- International Geological Congress Toronto, Ont.) 1913-
- International Geological Congress Vienna, Austria) 1903-
- International Geological Correlation Programme. Project no. 53 "Ecostratigraphy".
- International Harvester Company of America.
- International harvester company of America.
- International harvester company of New Jersey. Agricultural extension dept.
- International Harvester Company of New Jersey. Agriculture extension dept.
- International Harvester Company.
- International High Altitude Expedition to Chile (1935)
- International Hoya Association.
- International Indian Ocean Expedition 1960-1965
- International Indian Ocean Expedition ǂd (1960-1965),
- International Institute of Agriculture.
- International Institute of Agriculture. Bureau of Agricultural Intelligence and Plant Diseases
- International Institute of Agriculture. Bureau of Agricultural Intelligence and Plant Diseases.
- International Institute of Agriculture. Bureau of Agricultural Science and Practice
- International Institute of Agriculture. Bureau of Agricultural Science.
- International Institute of Agriculture. Bureau of Economic and Social Intelligence.
- International Institute of Differing Civilizations
- International Institute of Tropical Forestry (Río Piedras, San Juan, P.R.)
- International Legume Conference Saint Louis, Mo.) 1986-
- International Lepidoptera Survey.
- International Library of Technology.
- International Live Stock Exposition.
- International Marine Biological Workshop 6th 1993 Darwin N T-
- International Marine Biological Workshop (6th : 1993 : Darwin, N.T.)
- International Martes Symposium Edmonton, Alta.) 1995-
- International Martes Symposium.
- International Musselwatch Committee.
- International Mycological Conference University of Calgary) 1979-
- International Oceanographic Congress New York) 1959-
- International Organization Of Plant Biosystematists. International Symposium Saint Louis, Mo.) 1992-
- International Ornithological Committee.
- International Ornithological Congress Amsterdam, Netherlands) 1930-
- International Ornithological Congress Basel) 1954-
- International Ornithological Congress Berlin, Germany) 1978-
- International Ornithological Congress Budapest, Hungary 1891-
- International Ornithological Congress Christchurch, N.Z.) 1990-
- International Ornithological Congress Copenhagen, Denmark) 1926-
- International Ornithological Congress Helsinki, Finland) 1958-
- International Ornithological Congress London, England) 1905-
- International Ornithological Congress Moscow, Russia) 1982-
- International Ornithological Congress Oxford) 1966-
- International Ornithological Congress Uppsala) 1950-
- International Ornithological Congress.
- International Ornithological Congress. Standing Committee on Ornithological Nomenclature.
- International Pacific Halibut Commission.
- International Physiological Congress Liège, Belgium) 1892-
- International Phytogeographical Excursion 1913-
- International Phytogeographical Excursion (1st : 1911-
- International Polar Expedition 1882-1883
- International Polar Expedition to Point Barrow, Alaska (1881-1883)
- International Polar Expedition, 1882-1883
- International Rubber and Allied Trades Exhibition (3rd : 1912 : New York, N.Y.). Brazilian Commission.
- International Rubber and Allied Trades Exhibition. New York, N.Y. 1912-
- International Rubber Exhibition.
- International Seed Service.
- International Seed Testing Congress. Copenhagen, 1921-
- International seed testing congress. 3d, Copenhagen, 1921.
- International Seminar on Animal Import Risk Analysis Ottawa, Ont.) 1991-
- International Shrub Symposium Utah State University) 1971-
- International Society for Horticultural Science. Working Group on Fireblight Research.
- International Society for Stereology.
- International Society For The Study And Conservation Of Amphibians
- International Society of Arboriculture.
- International Society of Hymenopterists
- International Stock Food Co. (Minneapolis, Minn.)
- International Stock Food Company.
- International Symposium on Biological Control of Arthropods Christchurch, N.Z.) 2009-
- International Symposium on Biological Control of Weeds Bozeman, Mont.) 1999-
- International Symposium on Growth Lafayette, Ind.) 1960-
- International Symposium on Natural Mammalian Hibernation Dedham, Mass.) 1959-
- International Symposium on Nervous Inhibition Friday Harbor, Wash.) 1960-
- International Symposium on Ostracoda Aberystwyth) 1988-
- International symposium on Ostracoda Greenwich, England) 1997-
- International Symposium on Primary and Initial Effects of Ionizing Radiations on Living Cells Moscow, R.S.F.S.R.) 1960-
- International Symposium on Sustainability Santa Fe, N.M.) 1993-
- International Symposium On The Biology Of The Sipuncula Fort Pierce, Fla.) 2012-
- International Symposium on the Molecular Systematics of Bryophytes Missouri Botanical Garden) 2003-
- International Symposium on the Origin of Life on Earth Moscow). 1957-
- International Symposium on the Origin of Life on the Earth Moscow, R.S.F.S.R.) 1957-
- International Symposium on the Response of the Nervous System to Ionizing Radiation Chicago) 1960-