Unfortunately, it is too great a task to locate a shop that might contain some of the oils that Anjali recommended in her comment for remedies to my mosquito problem. One of the things you have to deal with when living in another country is not only is the language different, but things are different. For example, here you buy stamps and phone cards from tobacco shops, which also sell postcards and newspapers. At the grocery store, along with groceries, you find only a very limited selection of laundry and cleaning products, and certainly no aisle with housewares or cooking supplies or personal care items. For those, you have to find a drug store (not a pharmacy) and a housewares store. It is just different. That is why my brain cramps up just at the thought of hunting down almond oil, cedarwood oil, eucalyptus oil, pennyroyal oil, and human-grade citronella oil.
The citronella-infused dishcloth (see post titled "The canals are beautiful but...") worked for a while, but is wearing off. Last night, I was so desperate that I took the dishcloth and rubbed it on my arms and legs. I was worried about that because it is not cosmetic-citronella oil, it is meant to be burned in a diffuser. However, I suffered no ill effects for doing it for one night.
Today, I found this anti-mosquito device at a store. The writing on the back of the package is in Dutch and French so I'll translate from the French as to what this device is:
Inoffensive for humans and companion animals (pets), the Anti-Mosquito functions with ultrasounds. Chases away the mosquitos with ultrasounds without danger.
The device functions if the red LED is illuminated.
Ideal for an area of 25 meters squared outdoors and 50 meters squared inside.
Do not put the device behind an obsticle (Don't block the device).
Warning: Certain people or animals can be disturbed by ultrasound, mostly when too close to the device. To avoid this, it is advised to put the device further away, or to use it when the room is empty.
Let us hope this works.