Juglans californica Juglans californica Juglans californica, the California black walnut, also called the California walnut, or the Southern California black walnut, is a large shrub or small tree (up to 30 feet tall) of the walnut family, Juglandaceae, endemic to California. "Juglans californica" is generally found in the southern California Coast Ranges, Transverse Ranges, and Peninsular Ranges, and the Central Valley. It grows as part of mixed woodlands, and also on slopes and in valleys wherever conditions are favorable. It is threatened by development and overgrazing. Some native stands remain in urban Los Angeles in the Santa Monica Mountains and Hollywood Hills.
Two-sided market that the greater the multihoming costs, the greater is the tendency toward market concentration. Higher multihoming costs reduce user willingness to maintain affiliation with competing networks providing similar services. Attracted by the prospects of large margins, platforms can try to compete to be the winner-take-all in two-sided markets with strong network effects. That means that one platform serves the mature networked market. Examples of the standards battles include VHS vs Betamax, Microsoft vs Netscape and the DVD market. Not all two-sided markets with strong positive network effects are optimially supplied by a single platform. Markets must have high multi-homing costs