In the original contexts, hard to access proof readings are difficult, only sometimes. For example trying to access and for the purpose of assessing, I had to remove one page of an over 200 page PDF document and load a better form of data here as follows;
Many thanks to the folks in Corvallis (1993) that must be given proper recognition for the data. The sourcing is here;
This is a mostly blank page, many of which give us the opportunity to find other failures or success reports of our own. For example some of us find 'Eriobotrya' (or loquat) in the vertical section as "C" (compatible) where it's never reported (blank). "I" (incompatibles) are also encouraged to be reported. Any additional information such as age of graft and whether root sprouts are feeding energy to the rootstock can also be valuable when assessing recommended grafts.
I'll be the first. Apples on pear: per list, "P" (partial compatible).
This link has possibilities:
site:hort.purdue.edu/newcrop/janick-papers/c09.pdf even pear on apple stock
:I find the 50% crab cultivar malus 'palmetta' as very easy to graft both ways to pyrus asian/nashi pears 'ichiban' and a pass-a-long seedling of the same nashi type. I also have made good of grafting this crab on pyrus communis 'ohxf-513' when only pyrus nashi pear is the intermediate or the stock. I have zero failed experiences with this in either direction of pyrus to date. It is a very northern winter hardy apple of no fruit value in Alaska. From Alaska and other northern growers that have tried this idea (but) seem to fail with it. It causes the pyrus communis pear scions to become less winter hardy after 2 test winters.
My success locally stems from at least about the past 8 years where many other malus grafts in the same situation fail in the first year.