Many herbaria have initiatives to digitize specimens to produce a virtual herbarium. Most herbaria utilize a standard system of organizing their specimens into herbarium cases. Major herbaria are conserved at the National Botanic Gardens and the Ulster Museum. A herbarium ("plural" "herbaria") is a collection of preserved plant specimens. This approach is being increasingly used in collections in herbaria and botanic gardens. Many universities, museums, and botanical gardens maintain herbaria. Her specimens were widely distributed to herbaria throughout the United States and western Europe. In the past, botanists came here to collect plants for herbaria around the world. Modern herbaria often maintain electronic databases of their collections. Australia's museums, herbaria, royal societies, field naturalist clubs and government organisations make up the contributors. The Monimiaceae are underrepresented in herbaria and other plant collections. Plant collections are referred to as herbaria. Storage in metal cabinets is the best material to maintain herbaria collections. It is one of several State and Commonwealth herbaria in Australia. While at Cambridge he published several works, including "Libellus de re herbaria", in 1538.