Certaine rules, directions, or advertisments for this time of pestilentiall contagion: with a caueat to those that weare about their neckes impoisoned amulets as a preseruatiue from the plague: published for the behoofe of the city of London, and all other parts of the lan at this time visited; by Francis Hering, D. in Physicke, and Fellow of the Colledge of Phisitians in London.