This map shows the geographic impact of H.O. de Waal's research. It shows the number of citations coming from papers published by authors working in each country. You can also color the map by specialization and compare the number of citations received by H.O. de Waal with the expected number of citations based on a country's size and research output (numbers larger than one mean the country cites H.O. de Waal more than expected).
This network shows the impact of papers produced by H.O. de Waal. Nodes represent research fields, and links connect fields that are likely to share authors. Colored nodes show fields that tend to cite the papers produced by H.O. de Waal. The network helps show where H.O. de Waal may publish in the future.
Co-authorship network of co-authors of H.O. de Waal
This figure shows the co-authorship network connecting the top 25 collaborators of H.O. de Waal.
A scholar is included among the top collaborators of H.O. de Waal based on the total number of
citations received by their joint publications. Widths of edges
represent the number of papers authors have co-authored together.
Node borders
signify the number of papers an author published with H.O. de Waal. H.O. de Waal is excluded from
the visualization to improve readability, since they are connected to all nodes in the network.
Schwalbach, L.M.J., et al.. (2010). Effects of sun-dried Opuntia ficus-indica on feed and water intake and excretion of urine and faeces by Dorper sheep. South African Journal of Animal Science. 40(5). 491–494.15 indexed citations
4.
Waal, H.O. de, et al.. (2009). Herd management, milk production and reproduction of urban dairy farms in the Harar milkshed. ANIMAL PRODUCTION. 9(1). 57–75.3 indexed citations
5.
Schwalbach, L.M.J., et al.. (2006). A study of mineral status in the carcass of Boer goat bucks: influence of suplementation. Archivos de Zootecnia. 55(211). 313–316.5 indexed citations
6.
Schwalbach, L.M.J., H.O. de Waal, J.P.C. Greyling, & L. A. Cardoso. (2003). GROWTH AND CARCASS TRAITS OF YOUNG BOER GOAT BUCKS FED A DIET OF WINTER VELD HAY AND SUPPLEMENTED. Archivos de Zootecnia. 52(199). 393–396.1 indexed citations
7.
Waal, H.O. de. (1995). In sacco dry matter disappearanceo f herbagea nd maizem eal from the rumen of lactating Dorper and Merino ewess upplementedw ith protein and energy on native pasture. South African Journal of Animal Science. 25(1). 1–6.3 indexed citations
8.
Waal, H.O. de. (1994). The effects of long-term variation in rainfall and dry matter production of veld on the financial position of a beef weaner enterprise. South African Journal of Animal Science. 24(4). 113–118.3 indexed citations
9.
Waal, H.O. de. (1990). Animal production from native pasture (veld) in the Free State Region - A perspective of the grazing ruminant. South African Journal of Animal Science. 20(1). 1–9.25 indexed citations
10.
Waal, H.O. de, et al.. (1989). Supplementation of lactating Dorper and Merino ewes on Themeda cymbopogon veld. 2. Diet quality and feed intake. South African Journal of Animal Science. 19(4). 148–155.6 indexed citations
11.
Waal, H.O. de, et al.. (1989). Effects of sodium chloride on sheep. 1. Diet composition, body mass changes and wool production of young Merino wethers grazing native pasture. South African Journal of Animal Science. 19(1). 27–33.7 indexed citations
12.
Waal, H.O. de, et al.. (1989). Supplementation of lactating Dorper and Merino ewes on Themeda cymbopogon veld. 1. Body mass changes of ewes and their lambs. South African Journal of Animal Science. 19(4). 141–147.3 indexed citations
Waal, H.O. de, et al.. (1989). Effects of sodium chloride on sheep. 2. Voluntary feed intake and changes in certain rumen parameters of young Merino wethers grazing native pasture. South African Journal of Animal Science. 19(1). 34–42.8 indexed citations
Waal, H.O. de, et al.. (1987). The evaluation of dryland Cenchrus ciliaris l. cv Molopo for weaner calf production in the central grassveld.. African Journal of Range and Forage Science. 4(2). 55–58.1 indexed citations
17.
Waal, H.O. de, et al.. (1983). A note on the insertion of rumen cannulae in pregnant ewes. South African Journal of Animal Science. 13(4). 264–265.2 indexed citations
18.
Waal, H.O. de, et al.. (1981). Practical implications of the effect of drying and treatment on nitrogen content and in vitro digestibility of samples collected by oesophageally fistulated animals. South African Journal of Animal Science. 11(3). 247–254.20 indexed citations
19.
Waal, H.O. de, et al.. (1981). Supplementing sheep with protein and phosphorus on native pasture of the central Orange Free State. 2.Feed intake, mass changes and wool production*. South African Journal of Animal Science. 11(3). 217–227.11 indexed citations
20.
Waal, H.O. de, et al.. (1980). Supplementing sheep with protein and phosphorus on native pasture of the central Orange Free State. I. Diet composition, digestibility and rumen ammonia concentration. South African Journal of Animal Science. 10(2). 203–208.8 indexed citations
Rankless uses publication and citation data sourced from OpenAlex, an open and comprehensive
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incomplete records, variations in author disambiguation, differences in journal indexing, and
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Rankless may not fully capture the entirety of a scholar's output or impact.