Question: What is the city where the The Circle of Oak and Mistletoe (O&M) resides named after?

full_context: Document 1: Onkaparinga River: The Onkaparinga River, known as Ngangkiparri in the Kaurna language, is a river located in the Southern Adelaide region in the Australian state of South Australia.
Document 2: Circle of Oak and Mistletoe: The Circle of Oak and Mistletoe (O&M) is a Wiccan teaching coven based in Flagstaff Hill in the City of Onkaparinga; and an online teaching group and community. It is the founding coven of the Community Church of Inclusive Wicca which was incorporated in South Australia in 2008. Whilst primarily a group for Australian practitioners, it has evolved into a provider of teaching services globally.
Document 3: Donar's Oak: Jove's Oak ("interpretatio romana" for Donar's Oak and therefore sometimes referred to as Thor's Oak) was a sacred tree of the Germanic pagans located in an unclear location around what is now the region of Hesse, Germany. According to the 8th century "Vita Bonifatii auctore Willibaldi", the Anglo-Saxon missionary Saint Boniface and his retinue cut down the tree earlier the same century. Wood from the oak was then reportedly used to build a church at the site dedicated to Saint Peter. Sacred trees and sacred groves were widely venerated by the Germanic peoples.
Document 4: City of Onkaparinga: The City of Onkaparinga is a local government area (LGA) located on the southern fringe of Adelaide, South Australia. It is named after the Onkaparinga River, whose name comes from "Ngangkiparinga", a Kaurna word meaning women's river. It is the largest LGA in South Australia, with an estimated population of 164,800 people in both urban and rural communities and is also geographically expansive, encompassing an area of 518.3 km². The council is headquartered in the Noarlunga Centre with area offices situated in Aberfoyle Park, Woodcroft and Willunga.
Document 5: Onkaparinga River Recreation Park: Onkaparinga River Recreation Park is a protected area occupying land in the estuary of the Onkaparinga River in South Australia. The recreation park which was established in 1985 is approximately 32 km from Adelaide city centre. It is the venue for recreational activities such as walking, canoeing, kayaking, recreational fishing and picnics.
Document 6: Onkaparinga Hills, South Australia: Onkaparinga Hills is a southern suburb of Adelaide, in the City of Onkaparinga. It covers an area of approximately 22 km2 . It has a population of 2534 people (2011 Census). It is a leafy suburb that includes parts of the Onkaparinga River National Park.
Document 7: Port Noarlunga, South Australia: Port Noarlunga is a suburb in the City of Onkaparinga, South Australia. It is a small sea-side suburb, population 2,632, about 30 km to the south of the Adelaide city centre and was originally created as a sea port. This area is now popular as a holiday destination or for permanent residents wishing to commute to Adelaide or work locally. There is a jetty that connects to a 1.6 km long natural reef that is exposed at low tide. The beach is large and very long and has reasonable surfing in the South Port area whose name is taken from its location - 'South of the Port'.
Document 8: Onkaparinga River National Park: Onkaparinga River National Park is a protected area in the Australian state of South Australia located about 32 km south of Adelaide city centre. It extends over the floodplain of the Onkaparinga River east of Main South Road.
Document 9: Learning circle: The use of a circle as both the organizational structure and descriptive metaphor for a meeting of equals is likely to have been a part of our history for as long as fire has. The learning circle is a mechanism for organizing and honoring the collective wisdom of the group and is present in many indigenous cultures. For example, in early native councils of elders came together to understand problems in a spirit of shared community in “wisdom circles.” The term Learning Circle has been used to describe group efforts with clear links to social change . Over time and across countries, civic organizations, neighborhood communities, trade unions, churches and social justice groups have used the idea of learning circles to empower their members to make choices and take action. The web can help locate the many ways both present and past that groups have used the term Study circle or Learning Circle as a form of adult and student education. For example, Educators for Community Engagement, find that learning circles—with their principles of equal participation, reciprocity, and honoring of collective wisdom -embody the democratic principles of effective service-learning partnerships. They use learning circles, rather than more traditional forms of group meetings, to structure their annual conferences. Primary teachers use a simple form of learning circles when they gather the students at the rug for "circle time." However many educators are using learning circles to connect students from around the world. Among the goals of this activity are helping students to develop the trust and respect for diversity of experience, and fostering both listening and speaking skills among peers. Researchers have used learning circles as a form of professional development to improve their practice. A similar term, "Quality circle" was used in the 80's to characterize the successful practice in corporate settings in which the hierarchical boundaries between workers and managers are flattened to encourage participatory management and team leadership. Quality circles, originally associated with Japanese management and manufacturing techniques developed in Japan after world war II, based on lectures of W. Edwards Deming (Joel & Ross, 1982). The goal was to encourage everyone to develop a strong sense of ownership over the process and products of the group.
Document 10: Church of World Messianity: The Church of World Messianity (世界救世教 "Sekai Kyūsei Kyō" in Japanese), abbreviated COWM, is a Japanese new religion founded in 1935 by Mokichi Okada. There are three pillars of the religion, of which the key concept is johrei, claimed to be a method of channeling divine light into the body of another for the purposes of healing. The Art of Nature which includes nature farming, and the Art of Beauty which includes practices such as Ikebana, a form of Japanese flower arranging, are the other formal practices. In 1926, Okada claimed to have received a divine revelation that empowered him to be a channel of God's Healing Light ("johrei") to purify spiritual realm to remove the spiritual causes of illness, poverty, and strife from the world and inaugurate a new Messianic Age. He went on to teach Johrei to his followers allowing them also to achieve Messianity and spread the teachings across the world. Members are given permission to channel Johrei by wearing an O-Hikari pendant which contains a copy of one of Mokichi Okada's calligraphies. He is often referred to as "Meishu-Sama" (enlightened spiritual teacher) by his followers.
Document 11: Universel: The Universel is a temple of the Sufi Order International, located at The Abode of the Message (in the Berkshire Mountains near New Lebanon) a Universal Sufi community located in a former Shaker village. As well as the temple, there is also a conference centre, campground, forest huts and cabins, offices, retreat grounds, residential spiritual community of the order, Mountain Conference Center and the Abode Organic Farm.
Document 12: City of Onkaparinga: The City of Onkaparinga is a local government area (LGA) located on the southern fringe of Adelaide, South Australia. It is named after the Onkaparinga River, whose name comes from "Ngangkiparinga", a Kaurna word meaning women's river. It is the largest LGA in South Australia, with an estimated population of 164,800 people in both urban and rural communities and is also geographically expansive, encompassing an area of 518.3 km². The council is headquartered in the Noarlunga Centre with area offices situated in Aberfoyle Park, Woodcroft and Willunga.
Document 13: Oaksterdam, Oakland: Oaksterdam is a cultural district on the north end of downtown Oakland, California, where medical cannabis in a variety of competitively priced smokeable and edible preparations is available for purchase in multiple cafes, clubs, and patient dispensaries. Oaksterdam is located on the north end of downtown Oakland, between downtown proper, the Lakeside, and the financial district. It is roughly bordered by 14th Street on the southwest, Harrison Street on the southeast, 19th Street on the northeast, and Telegraph Avenue on the northwest. The name is a portmanteau of "Oakland" and "Amsterdam," the capital of the Netherlands, where marijuana is semi-legal. Founded in 2007, and located in the heart of Oakland, Oaksterdam University is the nation's first cannabis college. The school's mission is to provide quality training for the cannabis industry. Those interested in learning more about this emerging industry should learn to do so safely and responsibly in accordance with the law. At Oaksterdam University, state vs. federal law is the first class you are taught, in an effort to help you understand the law before you are taught anything else. The faculty at Oaksterdam University encompasses some of the most prominent names in the industry. Many of the faculty members not only helped write state law but also took medical marijuana cases to the Supreme Court. Oaksterdam University continues to educate, retaining its support from the city of Oakland.
Document 14: Mikawomma Reserve: The Mikawomma Reserve is found in the suburb of Woodville Gardens on the corner of Liberty Grove & Ridley Grove in South Australia, Australia. Mikawomma is the Kaurna name for the plain that lies between Adelaide and Port Adelaide (Teichelmann & Schürmann, 1840: 16 Grammar section). The Kaurna people are the traditional custodians of the Adelaide Plains area. The landscape design and the artworks in Mikawomma Reserve reflect indigenous plants and animals as well as culture and history.
Document 15: The Meeting House: The Meeting House is an Anabaptist church located in the Toronto suburb of Oakville, Ontario. It was founded in 1985 by Craig and Laura Sider, and was originally known as "Upper Oaks Community Church". With a consistent average weekly attendance of 4,400, it is ranked by the Hartford Institute of Religion as fourth among large churches (sometimes called megachurches) in Canada. Teaching (sermons) produced on the church's main Oakville campus is either simulcast or sent out on a one-week delay to nineteen satellite Ontario satellite locations, most of which meet in cinemas. The Meeting House is part of a denomination called the Be in Christ.
ground_truth: the Onkaparinga River