A fluorescent water base ink for ink-jet recording includes water, a first fluorescent dye, and a second fluorescent dye. Also disclosed is a method of making a bending wave panel-form acoustic radiator, comprising forming a sheet into a panel having at least one integral corrugation member extending out of the plane of the sheet and at least partly across the sheet and of substantially U-shape cross-section, to stiffen the sheet to have a desired ability to support and propagate bending waves. The first electronic communication may include at least one of a telephone call, a telephone call containing data, and a data message.